tag:blogger.com,1999:blog-25161887301401640762015-03-29T06:23:10.825-04:00Devlin's AngleDevlin's Angle is a monthly column sponsored by the Mathematical Association of America. Mathematician Keith Devlin is the Executive Director of the Human-Sciences and Technologies Advanced Research Institute (H-STAR) at Stanford University and The Math Guyon NPR's Weekend Edition.Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.comBlogger44125tag:blogger.com,1999:blog-2516188730140164076.post-42479147602837436032015-03-09T00:00:00.000-04:002015-03-16T11:17:38.214-04:00Pi Day, Cyclical Motion, and a Great Video Explanation of Multiplication<div class="separator" style="clear: both; text-align: center;"><a href="http://4.bp.blogspot.com/-wgUFZVC_bxk/VP8JvCHQ0ZI/AAAAAAAAKUQ/ZzLh7eYR4wI/s1600/Leibniz.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://4.bp.blogspot.com/-wgUFZVC_bxk/VP8JvCHQ0ZI/AAAAAAAAKUQ/ZzLh7eYR4wI/s1600/Leibniz.jpg" height="240" width="320" /></a></div><br />March 14 is Pi Day, the day in the year when we celebrate the world’s most famous mathematical constant.<br /><br />Back in 1988, on March 14, a physicist called Larry Shaw organized the first Pi Day celebration at the Exploratorium in San Francisco, where he worked. It was meant to be just a one-off, fun event to get kids interested in math. Children were invited in to march around one of the Exploratorium’s circular rooms and end up eating fruit pies. But the idea took off, and ever since, March 14 has been Pi Day. Not just at the Exploratorium, but with celebratory events organized all across the United States, and in other parts of the world.<br /><br />In case you haven’t twigged it, we celebrate Pi Day on March 14 because, in American date format, that day is 3.14, which is pi to two decimal places.<br /><br />This year is a particularly special, once-in-a-century Pi Day, since the American format date this year is 3.14.15, pi to four decimal places. If you want more pi-accuracy, drink a toast to pi at time 9:26:53 (AM or PM), to get the first nine places 3.141592653.<br /><br />That degree of accuracy, by the way, is more than enough for practical purposes. If you use that value to calculate the circumference of the Earth, the answer will be accurate to within 1/4 inch.<br /><br />Though we have known since the 18<sup>th</sup> Century that pi is irrational (indeed, transcendental, thereby demonstrating that you cannot square a circle), calculating approximate values of pi has a long history. In ancient times, Babylonians, Egyptians, Greeks, Indians, and Chinese mathematicians calculated the first three or four places, and found fraction approximations like 22/7 and 355/113.<br /><br />In the 16<sup>th</sup> century, a German who presumably had a lot of time on his hands spent most of his life computing pi to 36 places, and a 19<sup>th</sup> century American went all the way to 707 places, but he mad a mistake after 527 places, so the last part of his answer was wrong.<br /><br />In more recent times, computers have been used to compute pi to well over a trillion places, in part for sport, but also to test the accuracy of high speed supercomputers.<br /><br />Of course, PI Day isn’t really just about pi, it’s an excuse to celebrate all of mathematics, and in particular stimulate interest in mathematics among children and young adults. You will find Pi Day events in schools and colleges, at science museums, and other venues. Teachers, instructors, and students organize all kinds of math-related events and competitions. The value of pi simply sets the date.<br /><br />With this year’s special Century edition, some large organizations are putting on celebratory events, among them the Museum of Mathematics in New York City (details of the event <a href="https://in.momath.org/civicrm/event/info?reset=1&id=386" target="_blank">here</a>), the Computer History Museum just south of San Francisco (details <a href="http://www.computerhistory.org/events/upcoming/#pi-day-celebration" target="_blank">here</a>), and the NASA Space Center in Houston (see <a href="http://spacecenter.org/cosmic-spring-break/pi-day/" target="_blank">here</a>). And at the big <a href="http://teachingandlearning2015.org/" target="_blank">Teaching and Learning Conference</a> in Washington D.C. this week, I’m hosting a Pi Celebration at 8:00AM on Saturday morning.<br /><br />There are many other celebrations. Check to see what is going on in your area. If there is a large science or technology organization nearby, they may well be putting on a Pi Day event.<br /><br />The media have been getting in on the act too. NPR will air one of my short <a href="http://web.stanford.edu/~kdevlin/MathGuy.html" target="_blank">Math Guy</a> conversations with Weekend Edition host Scott Simon this Saturday morning, and today’s New York Times ran a <a href="http://wordplay.blogs.nytimes.com/2015/03/09/%CF%80/?_r=0" target="_blank">substantial article</a> about pi by their regular Numberplay contributor Garry Antonick.<br /><br />Antonick led off with a short pi-related problem I provided him with, and in honor of the Pi Day of the Century, in place of the traditional photo of me at a blackboard, he picked an action shot of me cresting a mountain on a bicycle (pi motion if ever there were) in a Century (100 mile) ride back in 2013.<br /><br />He could not resist bringing in the famous Euler Identity, linking the five most significant constants of mathematics, <i>pi</i>, <i>e</i>, <i>i</i>, 0, and 1. This has always been my favorite mathematical identity, and Antonick quotes from a magazine article I wrote about it a few years ago.<br /><br />But truth be told, it is not my favorite pi fact. For the simple reason, it’s not really about pi, rather it is about multiplication and exponentiation. Pi gets in because both operations involve the number.<br /><br />My favorite pi fact, ever since I first came across it as a teenager (one of several eye-opening moments that motivated me to become a mathematician), is Leibniz’s series (sometimes called Gregory’s series), which dates from the 17<sup>th</sup> century. You write down an endless addition sum that starts out 1/1, minus 1/3, plus 1/5, minus 1/7, plus 1/9, etc. All the reciprocals of the odd numbers, with alternating signs.<br /><br />Since this sum goes on for ever, you can’t actually add it up term by term, but you can use mathematical techniques to determine the answer a different way. And that answer is pi/4.<br /><br />What does pi have to do with adding the reciprocals of the odd numbers? As with Euler’s Identity, Leibniz’s series provides a glimpse of the deep structure of numbers and arithmetic that lies just beneath the surface.<br /><br />Talking of which, I caused a huge stir a few years ago when I ran a series of Devlin’s Angle posts trying to rid people (in particular, math teachers) of their false (and educationally dangerous) belief that multiplication is repeated addition (and exponentiation is repeated multiplication).<br /><br />The initial series ran in <a href="http://www.maa.org/external_archive/devlin/devlin_06_08.html" target="_blank">June</a>, <a href="http://www.maa.org/external_archive/devlin/devlin_0708_08.html" target="_blank">July-August</a>, and <a href="http://www.maa.org/external_archive/devlin/devlin_09_08.html" target="_blank">September</a> 2008. When the barrage of facts I referenced in the third of those posts failed to stem the flood of disbelieving reactions of readers, I ran a lengthy post in <a href="http://www.maa.org/external_archive/devlin/devlin_01_11.html" target="_blank">January 2011</a> trying to convey the truly deep (and powerful) structure of multiplication.<br /><br />Still to little avail. Put repeated addition in the same bin as evolution by natural selection, climate change, and the <a href="https://www.maa.org/external_archive/devlin/devlin_05_07.html" target="_blank">Golden Ratio</a>. For many people, no amount of facts can overturn a long held and cherished belief. It’s a common human trait – fortunately not a universal one, else we’d still be living in caves and mud huts. (A politician who says “I am not a scientist” is effectively saying “I don’t understand the difference between building my mansion and a mud hut.”)<br /><br />Unfortunately, as a wordsmith, I did not, and do not, possess the skill to provide a really good explanation of multiplication. I had to resort to spinning a multi-faceted story based on scaling. Someone who does have what it takes to tell the story properly, using video, is Stanford mathematics and computer science senior undergraduate <a href="https://www.youtube.com/channel/UCYO_jab_esuFRV4b17AJtAw/about" target="_blank">Grant Sanderson</a>. His recent <a href="https://www.youtube.com/watch?v=F_0yfvm0UoU" target="_blank">video on Euler’s Identity</a> is the best explanation of addition and multiplication I have ever seen. Period. Antonick embeds it in his New York Times piece. It deserves widespread circulation.<br /><br />The video actually goes on to discuss the exponential function, and then the Euler Identity, but I suspect many viewers will get lost at that point. The exponential function is pretty sophisticated. Much more so than addition and multiplication. In contrast, all it takes to understand those two staples of modern numerical life is to get beyond the ultimately misleading concepts many of us form in the first few years of our lives. Do that, and Sanderson’s video provides the rest.<br /><br />As is so often said, a picture can be worth a thousand words. Sanderson demonstrates that a motion picture can be worth a hundred thousand.<br /><br />NOTE: I did try song a few years ago, collaborating with a Santa Cruz choral group called Zambra. The result can be found <a href="http://web.stanford.edu/~kdevlin/HE.html" target="_blank">here</a>. There’s lots of pi stuff in those compositions. But it’s primarily musical interpretation of mathematics, not explanation. (For instance, check out our rendering of <a href="http://web.stanford.edu/~kdevlin/HE_QTmovies/Part_5.mp4" target="_blank">Leibniz’s series</a>.)<br /><br />Finally, I often get asked why we use the Greek letter pi to denote the ratio of the circumference of a circle to its <i>perimeter</i> of a circle to its diameter.. This convention goes back to the 18<sup>th</sup> Century.<br /><br />Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com1tag:blogger.com,1999:blog-2516188730140164076.post-56671549658580896102015-02-01T00:00:00.000-05:002015-02-17T13:24:45.679-05:00The Greatest Math Teacher Ever?<em>Last month I wrote about the kind of mathematic learning experiences we need to design to prepare young people for life in the Twenty-First Century. I cited the hugely successful, pioneering educational work of the late Professor R L Moore of the University of Texas. This follow up article about Moore and his teaching method is a combination of two earlier Devlin’s Angle posts, from <a href="http://www.maa.org/external_archive/devlin/devlin_5_99.html" target="_blank">May 1999</a> and <a href="http://www.maa.org/external_archive/devlin/devlin_6_99.html" target="_blank">June 1999</a>. Other than adding a short paragraph at the end leading to further information about Moore, the only changes to my original text are minor updates to adjust for the passage of time.</em><br /><br /><b>The set-up</b><br /><br />Each year, the MAA recognizes great university teachers of mathematics. Anybody who has been involved in selecting a colleague for a teaching award will know that it is an extremely difficult task. There is no universally agreed upon, ability-based linear ordering of mathematics teachers, even in a single state in a given year. How much more difficult it might be then to choose a “greatest ever university teacher of mathematics.” But if you base your decision on which university teacher of mathematics has had (through his or her teaching) the greatest impact on the field of mathematics, then there does seem to be an obvious winner. Who is it?<br /><br />Most of us who have been in mathematics for over thirty years probably know the answer. Let me give you some clues as to the individual who, I am suggesting, could justifiably be described as the American university mathematician who, through his (it’s a man) teaching, has had the greatest impact on the field of mathematics.<br /><br />He died in 1974 at the age of 91. <br /><br />He was cut in the classic mold of the larger-than-life American hero: strong, athletic, fit, strikingly good looking, and married to a beautiful wife (in the familiar Hollywood sense). <br /><br />He was well able to handle himself in a fist fight, an expert shot with a pistol, a lover of fast cars, self-confident and self-reliant, and fiercely independent. <br /><br />Opinionated and fiercely strong-willed, he was forever embroiled in controversy. <br /><br />He was extremely polite; for example, he would always stand up when a lady entered the room. <br /><br />He was a pioneer in one of the most important branches of mathematics in the twentieth century. <br /><br />He was a elected to membership of the National Academy of Science, as were three of his students. <br /><br />The method of teaching he developed is now named after him. <br /><br />If you measure teaching quality in terms of the product - the successful students - our man has no competition for the title of the greatest ever math teacher. During his 64 year career as a professor of mathematics, he supervised fifty successful doctoral students. Of those fifty Ph.D.’s, three went on to become presidents of the AMS - a position our man himself held at one point - and three others vice-presidents, and five became presidents of the MAA. Many more pursued highly successful careers in mathematics, achieving influential positions in the AMS and the MAA, producing successful Ph.D. students of their own and helping shape the development of American mathematics as it rose to its present-day position of world dominance.<br /><br />In the first half of the Twentieth Century, fully 25% of the time the president of the MAA was either a student or a grandstudent of this man. <br /><br />Other students and grandstudents of our mystery mathematician served as secretary, treasurer, or executive director of one of the two mathematical organizations and were editors of leading mathematical journals. <br /><br />After reaching the age of 70, the official retirement age for professors at his university, in 1952, he not only continued to teach at the university, he continued to teach a maximum lecture load of five courses a year - more than most full-time junior faculty took on. He did so despite receiving only a half-time salary, the maximum that state regulations allowed for someone past retirement age who for special reasons was kept on in a “part-time” capacity. <br /><br />He maintained that punishing schedule for a further eighteen years, producing 24 of his 50 successful Ph.D. students during that period. <br /><br />He only gave up in 1969, when, after a long and bitter battle, he was quite literally forced to retire. <br /><br />In 1967, the <em>American Mathematical Monthly</em> published the results of a national survey giving the average number of publications of doctorates in mathematics who graduated between 1950 and 1959. The three highest figures were 6.3 publications per doctorate from Tulane University, 5.44 from Harvard, and 4.96 from the University of Chicago. During that same period, our mathematician’s students averaged 7.1. What makes this figure the more remarkable is that our man had reached the official retirement age just after to the start of the period in question.<br /><br />Who was he? <br /><br /><strong>The answer</strong><br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="http://1.bp.blogspot.com/-8eVQb6UIN0o/VONKKMYZxOI/AAAAAAAAKTI/bbvlekI4yzE/s1600/Feb15_RLM.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="http://1.bp.blogspot.com/-8eVQb6UIN0o/VONKKMYZxOI/AAAAAAAAKTI/bbvlekI4yzE/s1600/Feb15_RLM.jpg" /></a></div>His name is Robert Lee Moore. Born in Dallas in 1882, R. L. Moore (as he was generally known) stamped his imprint on American mathematics to an extent that only in his later years could be fully appreciated. <br /><br />As I noted earlier, during 64 year career, the last 49 of them at the University of Texas, Moore supervised fifty successful doctoral students. Three of them went on to become presidents of the AMS (R. L. Wilder, G. T. Whyburn, R H Bing) -- a position Moore also held -- and three others vice-presidents (E. E. Moise, R. D. Anderson, M. E. Rudin), and five became presidents of the MAA (R. D. Anderson, E. Moise, G. S. Young, R H Bing, R. L. Wilder). Many more pursued highly successful careers in mathematics, achieving influential positions in the AMS and the MAA, producing successful Ph.D. students of their own -- mathematical grandchildren of Moore -- and helping shape the development of American mathematics as it rose to its present-day dominant position. That’s quite a record!<br /><br />In 1931 Moore was elected to membership of the National Academy of Science. Three of his students were also so honored: G. T. Whyburn in 1951, R. L. Wilder in 1963, and R H Bing in 1965. <br /><br />In 1973, his school, the University of Texas at Austin, named its new, two-winged, seventeen-story mathematics, physics, and astronomy building after him: Robert Lee Moore Hall. This honor came just over a year before his death. The Center for American History at the University of Texas has established an entire collection devoted to the writings of Moore and his students. <br /><br /><strong>Discovery learning</strong><br /><br />Moore was one of the founders of modern point set topology (or general topology), and his research work alone puts him among the very best of American mathematicians. But his real fame lies in his achievements as a teacher, particularly of graduate mathematics. He developed a method of teaching that became widely known as “the Moore Method”. Its present-day derivative is often referred to as “Discovery Learning” or “Inquiry-Based Learning” (IBL).<br /><br />One of the first things that would have struck you if you had walked into one of Moore’s graduate classes was that there were no textbooks. On each student’s desk you would see the student’s own notebook and nothing else! To be accepted into Moore’s class, you had to commit not only not to buy a textbook, but also not so much as glance at any book, article, or note that might be relevant to the course. The only material you could consult were the notes you yourself made, either in class or when working on your own. And Moore meant alone! The students in Moore’s classes were forbidden from talking about anything in the course to one another -- or to anybody else -- outside of class. Moore’s idea was that the students should discover most of the material in the course themselves. The teacher’s job was to guide the student through the discovery process in a modern-day, mathematical version of the Socratic dialogue. (Of course, the students did learn from one another during the class sessions. But then Moore guided the entire process. Moreover, each student was expected to have attempted to prove all of the results that others might present.)<br /><br />Moore’s method uses the axiomatic method as an instructional device. Moore would give the students the axioms a few at a time and let them deduce consequences. A typical Moore class might begin like this. Moore would ask one student to step up to the board to prove a result stated in the previous class or to give a counterexample to some earlier conjecture -- and very occasionally to formulate a new axiom to meet a previously identified need. Moore would generally begin by asking the weakest student to make the first attempt -- or at least the student who had hitherto contributed least to the class. The other students would be charged with pointing out any errors in the first student’s presentation.<br /><br />Very often, the first student would be unable to provide a satisfactory answer -- or even any answer at all, and so Moore might ask for volunteers or else call upon the next weakest, then the next, and so on. Sometimes, no one would be able to provide a satisfactory answer. If that were the case, Moore might provide a hint or a suggestion, but nothing that would form a constitutive part of the eventual answer. Then again, he might simply dismiss the group and tell them to go away and think some more about the problem. <br /><br />Moore’s discovery method was not designed for -- and probably will not work in -- a mathematics course which should survey a broad area or cover a large body of facts. And it would obviously need modification in an area of mathematics where the student needs a substantial background knowledge in order to begin. But there are areas of mathematics where, in the hands of the right teacher -- and possibly the right students -- Moore’s procedure can work just fine. Moore’s own area of general topology is just such an area. You can find elements of the Moore method being used in mathematics classes at many institutions today, particularly in graduate courses and in classes for upper-level undergraduate mathematics majors, but few instructors ever take the process to the lengths that Moore did, and when they try, they rarely meet with the same degree of success.<br /><br />Part of the secret to Moore’s success with his method lay in the close attention he paid to his students. Former Moore student William Mahavier (now deceased) addressed this point:<br /><br />“Moore treated different students differently and his classes varied depending on the caliber of his students. . . . Moore helped his students a lot but did it in such a way that they did not feel that the help detracted from the satisfaction they received from having solved a problem. He was a master at saying the right thing to the right student at the right time. Most of us would not consider devoting the time that Moore did to his classes. This is probably why so many people claim to have tried the Moore method without success.”<br /><br />Another famous (now deceased) mathematician who advocated -- and has successfully used -- (a modern version of) the Moore method was Paul Halmos. He wrote: <br /><br />“Can one learn mathematics by reading it? I am inclined to say no. Reading has an edge over listening because reading is more active -- but not much. Reading with pencil and paper on the side is very much better -- it is a big step in the right direction. The very best way to read a book, however, with, to be sure, pencil and paper on the side, is to keep the pencil busy on the paper and throw the book away.”<br /><br />Of course, as Halmos went on to admit, such an extreme approach would be a recipe for disaster in today’s over-populated lecture halls. The educational environment in which we find ourselves these days would not allow another R. L. Moore to operate, even if such a person were to exist. Besides the much greater student numbers, the tenure and promotion system adopted in many (most?) present-day colleges and universities encourages a gentle and entertaining presentation of mush, and often punishes harshly (by expulsion from the profession) the individual who seeks to challenge and provoke -- an observation that is made problematic by its potential for invocation as a defense for genuinely poor teaching. But as numerous mathematics instructors have demonstrated, when adapted to today’s classroom, the Moore method -- discovery learning -- has a lot to offer.<br /><br />If you want to learn more about R. L. Moore and his teaching method, check out the web site: <a href="http://legacyrlmoore.org/">http://legacyrlmoore.org/</a>. <br /><br />But before you give the method a try, take heed of the advice from those who have used it: Plan well in advance and be prepared to really get to know your students. Halmos put it this way: <br /><br />“If you are a teacher and a possible convert to the Moore method ... don’t think that you’ll do less work that way. It takes me a couple of months of hard work to prepare for a Moore course. ... I have to chop the material into bite-sized pieces, I have to arrange it so that it becomes accessible, and I must visualize the course as a whole -- what can I hope that they will have learned when it’s over? As the course goes along, I must keep preparing for each meeting: to stay on top of what goes on in class. I myself must be able to prove everything. In class I must stay on my toes every second. ... I am convinced that the Moore method is the best way to teach there is -- but if you try it, don’t be surprised if it takes a lot out of you.”<br /><br /><strong>There is a caveat</strong><br /><br />When I wrote those two Devlin’s Angle posts back in 1999, I debated with myself whether to address a side to the Moore story that, particularly from a late Twentieth Century perspective, does not stand to his credit. The issue is race. <br /><br />Moore’s racial attitude was nothing unusual for a white person who was born and lived most of his life in Texas in the late Nineteenth Century and the first three quarters of the Twentieth. When the Civil Rights Act was passed in 1964 (yes, that recently!), making racial discrimination illegal, Moore was already long past retiring age, and just five years short of actually vacating his university office. Moreover, no one who regularly reads a newspaper would believe that racial discrimination in America is a thing of the past. Moore’s racial views are still not unusual in Texas and elsewhere. <br /><br />Were Moore not such a towering figure, his position on race (at least as demonstrated by his actions) would not merit attention. But like all great people, all aspects of his life become matters of scrutiny. Moore could have acted differently when it came to race, even back then, in Texas, but he did not. And from today’s perspective, that inevitably leaves an uncomfortable stain on his legacy. <br /><br />In writing my two 1999 columns, I chose to focus on Moore the university teacher, in particular to raise awareness of discovery learning in mathematics. The focus of Devlin’s Angle is, after all, mathematics and mathematics teaching. I did not want to distract from that goal with what is clearly a side issue, particularly such an explosive one. Moore’s larger-than-life character was clearly a significant part of his success. His racism (or at least racist behavior) was not a part of that success story – if for no other reason than because he never accepted any Black students. So I did not raise the issue. <br /><br />For the same reason, I have left this side of the Moore story to the end here. We can learn from Moore when it comes to designing good mathematics learning experiences, and even admire him as a highly gifted teacher, without condoning other aspects of his life, just as we can enjoy Wagner’s music without endorsing Nazism. I can however leave you with a pointer to an <a href="http://www.math.buffalo.edu/mad/special/RLMoore-racist-math.html" target="_blank">article</a> posted online by Mathematics Professor Scott Williams on 5/28/99, about the same time my articles appeared (and possibly in response to the first of them). Like it or not, Williams’ post shines light on another side to the Moore story. We can learn things from great people in ways other than taking a class from them, and we can perhaps learn things they were not trying to teach us. <br /><br /><strong>References</strong><br /><br />Paul R. Halmos (1975), The Problem of Learning to Teach: The Teaching of Problem Solving, <em>American Mathematical Monthly</em>, Volume 82, pp.466-470. <br />Paul R. Halmos (1985), <em>I Want to Be a Mathematician</em>, Chapter 12 (How to Teach), New York: Springer-Verlag, pp.253-265. <br />William S. Mahavier (1998), What is the Moore Method?, The Legacy of R. L. Moore Project, Austin, Texas: The University of Texas archives. <br /><br />Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com1tag:blogger.com,1999:blog-2516188730140164076.post-73280691286428700182015-01-01T00:00:00.000-05:002015-01-03T12:18:12.901-05:00Your Father’s Mathematics Teaching No Longer Works<i>Gender-challenged title courtesy of this famous 1988 Oldsmobile TV commercial:</i><br /><br /><div style="text-align: center;"><iframe allowfullscreen="" frameborder="0" height="315" src="//www.youtube.com/embed/bAJ3-mbP1pY" width="560"></iframe></div><br />The start of a New Year is traditionally a time when we resolve to make changes. Change is particularly imperative in US mathematics education, which is built on a (Nineteenth Century) pedagogic model that long since passed its expiry date.<br /><br />In a nutshell, the school system we all grew up with was essentially developed in Nineteenth Century Britain to provided a global infrastructure to run the British Empire. In modern terms, the British Imperialists created an “Internet” and an “Internet of Things” using the best computational and manufacturing resources available at the time: people.<br /><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://3.bp.blogspot.com/-RJnMC765zcQ/VKRBDS08HjI/AAAAAAAAKSY/sqPwde7hN_4/s1600/BritishEmpire1922.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://3.bp.blogspot.com/-RJnMC765zcQ/VKRBDS08HjI/AAAAAAAAKSY/sqPwde7hN_4/s1600/BritishEmpire1922.jpg" height="301" width="500" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;">Controlled by an “Internet of human computers”: The British Empire in 1922.<br />Map from <a href="http://trivto.deviantart.com/" target="_blank">trivto.deviantart.com</a>.</span></td></tr></tbody></table>While few of us in K-16 education today see it as merely a process to prepare young people for work, we inherited a system built to do just that. <br /><br />Now we have an electronic, digital Internet, does it make sense to continue to use the old system? <br /><br />What do Twenty-First Century citizens need from their education? <br /><br />While not the only thing—not even close—equipping young people for work is still an important educational goal, both for the individual and for society as a whole. Accordingly, it makes sense for those of us in systemic education to be constantly aware of the skills that are actually required in the workplace. If those skills change, so should the education we provide. <br /><br />A good place to start is by asking the leaders of the leading companies what they look for when hiring new employees. The table below shows us what skills the Fortune 500 companies were asking for in 1970, then again thirty years later in 1999. <br /><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-66atIwXiVZo/VKRBkPopK0I/AAAAAAAAKSg/KVNnVihH4-o/s1600/Fortune500.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://1.bp.blogspot.com/-66atIwXiVZo/VKRBkPopK0I/AAAAAAAAKSg/KVNnVihH4-o/s1600/Fortune500.png" height="220" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: x-small;">Fortune 500 most valued skills, cited in<br />Linda Darling-Hammond et al, <a href="http://www.testpublishers.org/assets/criteria-higher-quality-assessment_1.pdf" target="_blank">Criteria for High-Quality Assessment</a> (2013)</span></td></tr></tbody></table><div class="separator" style="clear: both; text-align: center;"></div><br />It makes for dramatic reading. While the required skills ranked from 4 through 9 remained unaltered, the top three changed completely. The most important skill in 1970, writing, dropped to number 10, while skills two and three, computation and reading, respectively, dropped off the top ten list entirely.<br /><br />The most important skill in the workplace at the start of the Twenty-First Century, according to those leading companies, is teamwork, which in a single generation had leapt up from number 10. The other two skills at the top, Problem Solving and Interpersonal Skills, were not even listed back in 1970. <br /><br />Clearly, the world (of work) has changed, at least for those of us living in advanced societies. Unfortunately, for those of us in the United States, and many other parts of the world, our education system has failed to keep up. <br /><br />In large part, this is because of the hard-to-avoid inertia that so often comes with national (or statewide) education systems. By and large, many politicians and bureaucrats are far less aware of rapidly changing workforce requirements than those in business, and politicians frequently pander to the often woefully uninformed beliefs of voters, who tend to resist change–especially change that will affect their children.<br /><br />In the US, we see this dramatically illustrated by the widespread resistance to the Common Core State Standards. In the case of mathematics, just look at how closely the eight basic <a href="http://www.corestandards.org/Math/Practice/" target="”_blank”">Mathematics Principles</a> of the CCSS align to that Fortune 500 list of required Twenty-First Century skills:<br /><ol><li>Make sense of problems and persevere in solving them.</li><li>Reason abstractly and quantitatively.</li><li>Construct viable arguments and critique the reasoning of others.</li><li>Model with mathematics.</li><li>Use appropriate tools strategically.</li><li>Attend to precision.</li><li>Look for and make use of structure.</li><li>Look for and express regularity in repeated reasoning.</li></ol>The fact is, any parent who opposes adoption of the CCSS is, in effect, saying, “I do not want my child prepared for life in the Twenty-First Century.” They really are. Not out of lack of concern for their children, to be sure. Quite the contrary. Rather, what leads them astray is that they are not truly aware of how the huge shifts that have taken place in society over the last thirty years have impacted educational needs.<br /><br />Having lived through those changes, parents have (for the most part) been able to build on their own education and cope with new demands. “What worked for me will work for my children,” they say. (They say that even when it patently did not work for them!) <br /><br />But the situation is very different for their children. They are being thrust straight into that new world. To prepare them for that, you need a very different kind of education: one based on understanding rather then procedural mastery, and on exploration rather than instruction.<br /><br />One of the best summaries of this societal change, and the resulting need for educational shift, that I know is the 22 minutes TED Talk <a href="http://www.ted.com/talks/sugata_mitra_build_a_school_in_the_cloud?language=en" target="_blank">Build a School in the Cloud</a>, given by the educational researcher Sugata Mitra, winner of the 2013 TED Prize. <br /><br />In his talk, not only does Mitra explain why we need to make radical changes to education, he provides examples, backed by solid evidence, of how a “Fortune 500 oriented,” team-based, exploratory approach works. In the late 1990s and throughout the 2000s, Mitra conducted experiments in which he gave children in India access to computers. Without any instruction, they were able to teach themselves a variety of things, from English to DNA replication. <br /><br />[See also Mitra’s <a href="http://www.ted.com/talks/sugata_mitra_the_child_driven_education" target="_blank">earlier talk</a> from 2010.] <br /><br /><a href="http://www.ted.com/talks/ken_robinson_changing_education_paradigms" target="_blank">Another good account</a> of this need for educational change is provided by Sir Ken Robinson, also in a TED Talk (11 minutes). <br /><br />These ideas are not new. Indeed, they are mainstream in educational research circles. They just have not permeated society at large. <br /><br />For instance, Harvard physicist Eric Mazur has been teaching by Inquiry-Based Learning (IBL), to use one of several names for this general approach, for over twenty-five years, since he first noticed that instructional lectures simply do not work. He describes his approach, and the reasons for adopting it, in his 2009 talk <a href="https://www.youtube.com/watch?v=rvw68sLlfF8" target="_blank">Confessions of a Converted Lecturer</a> (18 minutes, abridged version). <br /><br />In mathematics, the IBL approach goes way back to the 1920s. I wrote about the best known proponent in two Devlin’s Angle posts back in 1999: <a href="http://www.maa.org/external_archive/devlin/devlin_5_99.html" target="_blank">May</a>, <a href="http://www.maa.org/external_archive/devlin/devlin_6_99.html" target="_blank">June</a>. <br /><br />Moore’s ideas have been adapted and used successfully in present-day mathematics classrooms, as shown in the promotional video <a _blank="" href="https://www.youtube.com/watch?v=f6t6WiWYdgY" target="_blank">Creativity in Mathematics: Inquiry-Based Learning and the Moore Method</a> (20 minutes). <br /><br />Lest my account of R L Moore and that last video portrayal leaves you with the impression that IBL math is for bright college students, see also this <a href="http://www.wired.com/2013/10/free-thinkers/all/" target="_blank">WIRED magazine account</a> of the success Mexican teacher Sergio Juárez Correa had when he took a Mitra inspired approach into a poor school in Matamoros, a city of half-a-million known more for its drug trade than for being at the forefront of Twenty-First Century mathematics education. <br /><br />Remember, Bob Dylan sang this in 1964: <br /><br /><div style="text-align: center;"><iframe allowfullscreen="" frameborder="0" height="315" src="//www.youtube.com/embed/e7qQ6_RV4VQ" width="420"></iframe></div><br /><br />AS OF TODAY, THAT’S OVER FIFTY YEARS AGO!<br /><br />It’s long past time for the education system to catch up with the world outside the classroom. That should be our resolution for 2015. <br /><br />Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com24tag:blogger.com,1999:blog-2516188730140164076.post-23090516678755385952014-12-10T10:00:00.007-05:002014-12-10T14:26:08.140-05:00How do you find good math learning apps?There are approximately 20,000 math learning apps available on the App Store (classified as such by their creators). Google Play does not provide the corresponding figure for Android apps, but presumably there are a lot there as well.<br /><br />Most of those apps do little more than provide repetitive practice of very basic skills, primarily about numbers. They are essentially just animated flash cards. <br /><br />How can a parent, or a teacher, decide which apps are likely to benefit their child, or their students? I’ll come back to that later. <br /><br />First, let me say that there is not necessarily anything wrong with an app that is essentially just an animated flash card – unless parents buy them (or just download them, as the majority are free) thinking that putting them on their children’s iPad or whatever <em>is all they need to do</em> to improve their performance in math. <br /><br />In the days when the gateway to mathematics, and indeed much of everyday life, lay in mastering the multiplication tables and memorizing a few formulas for calculating areas and volumes, mastery of the basic number facts was indeed enough to start with. So it’s a pity those fun learning apps were not available back then. They would have made the acquisition of those fundamental facts and skills so much easier and far more enjoyable. <br /><br />Unfortunately, the very digital technologies that have put those learning apps into eager young hands have also provided tools that have rendered procedural mastery of those basic skills all but irrelevant. <br /><br />In today’s world, we use cheap, ubiquitous devices to do our calculations. It’s no longer important that all members of society have procedural mastery of basic arithmetic. What is required is the ability to make effective use of those digital devices, and what that depends upon is a good understanding of number – what is often referred to as <em>number sense</em>. <br /><br />Roughly speaking, having number sense means being proficient with quantities and operations with numbers. A person with number sense is able to represent number concepts with models, words and diagrams, to communicate numerical ideas, and solve problems involving numbers. She or he can flexibly compose and decompose numbers for computation and solving problems. They can evaluate the reasonableness of solutions to numerical problems, and make connections between multiple solution methods. They can communicate their number sense verbally and in writing. They notice and explore number patterns, make connections and conjectures, and communicate their thinking to others. Number sense goes beyond solving word problems and memorizing basic facts and procedures. It involves engaging in numbers and operations in ways that develop a deep understanding of the content, which provides a firm foundation for mathematical success. In particular, a strong background in number sense sets the stage for later success in algebra and other parts of mathematics.<br /><br />If that last paragraph sounds like something that emerged from a committee of mathematics education experts, it is because in essence it did. You find language like that in the National Research Council’s 2000 report <a href="http://www.nap.edu/catalog/9822/adding-it-up-helping-children-learn-mathematics" target="_blank">Adding it Up</a>, (which you can download for free from the National Academies Press) and in the preamble to the <a href="http://www.corestandards.org/Math/" target="_blank">Common Core State Standards for Mathematics</a>, which emphasize the development of number sense in young children. <br /><br />For sure, you cannot have number sense without being able to solve an arithmetic problem and get the right answer. What has changed is that it is no longer important to solve that problem by the fastest method, or by a standard method that leaves a paper audit trail that others can check. Our calculating devices do those for us. <br /><br />Much more important in today’s world is to be able to reason about the numbers in a problem from first principles, in a way that embodies the internal structure of the numbers. For as humans, we need to be able to operate when and where that calculator cannot: namely, when we are faced with a novel problem the real world has thrown up at us. <br /><br />It was a lack of recognition that the world has changed fundamentally that led the consequently-Internet-famous “Jack’s Dad” to pen his satirical “letter to his son” that went viral on social media earlier this year. (See the next link below.) <br /><br />Actually, Jack’s dad is an electronics engineer, so he was certainly aware of how much today’s world was different from the days of his own childhood. Unfortunately, as someone outside the world of education, he had just not connected the dots to understand what changes in education were required in order to properly prepare today’s kids to live, not just in our present world, but in the world they will help shape from it. <br /><br />One of the best summaries of the issues behind that social media firestorm that I came across was the <a href="https://christopherdanielson.wordpress.com/2014/04/06/5-reasons-not-to-share-that-common-core-worksheet-on-facebook/" target="_blank">April 6 response</a> to Jack’s Dad written by the math education blogger Christopher Danielson. <br /><br />Danielson’s observations about different kinds of expertise rang very true to me. Having devoted the first part of my mathematics career to mathematical research, it was my appointment to serve on the Mathematical Sciences Education Board in 2000, and the close contact with leading experts in mathematics teaching that resulted, that brought home to me just how little I knew about how people learn mathematics, and how (consequently) we should teach it. <br /><br />Put plainly, having a PhD in mathematics and a string of published research is absolutely nothing like enough background to speak with authority about K-12 mathematics learning. People like me can provide good advice on mathematical content; but not on mathematics teaching. That requires different knowledge and expertise. <br /><br />My own university, Stanford, famous for its very high standards in research, apparently recognizes this when it comes to hiring new faculty in Education. While I cannot speak with authority for the School of Education’s policies, I have observed that no one gets appointed to the faculty who has not spent several years in K-12 teaching. (<em>In addition</em> to having done and published first class research!) Whether or not K-12 experience is official hiring policy, it certainly plays out that way, and it seems to me to be a sensible criterion to demand. <br /><br />Going back to the standard algorithms and Jack’s Dad, a few months after his first post, on October 8, Danielson posted <a href="https://christopherdanielson.wordpress.com/category/talking-math-with-your-kids/" target="_blank">another excellent blog</a> on the degree to which the position occupied by the standard arithmetic algorithms (in actual fact, there are many variations, so there is no such thing as “<em>the</em> standard algorithms) has changed in the educational landscape – from being the main focus as a method for daily use, to an interesting and historically important example of a set of highly efficient paper-and-pencil algorithms that quite literally changed the world. Their significance was a consequence of the dominant information storage and communication technology of the time: flat, static writing surfaces such as parchment, blackboards, and paper. (I describe that story in my book <a href="http://www.amazon.com/Man-Numbers-Fibonaccis-Arithmetic-Revolution/dp/0802778127/ref=sr_1_1?ie=UTF8&qid=1306990867&sr=8-1" target="_blank">The Man of Numbers</a>.) <br /><br />I will note, in passing, that Danielson’s October post indicates that some math learning apps may in fact do harm to a child’s mathematics learning, an observation that should be coupled with my earlier remarks about choosing basic skills educational apps. <br /><br />What put these thoughts onto my front burner recently were some discussions I was having with members of the Scientific Advisory Board for my educational technology startup company <a href="http://www.brainquake.com/" target="_blank">BrainQuake</a>. <br /><br />If you check out our company’s <a href="http://www.brainquake.com/our-team/" target="_blank">Team page</a>, you will find we have recruited a number of world renown experts in mathematics education. Now you may think they are just there for marketing purposes – website name dropping. But you would be wrong. Each one is there because they bring very valuable, very specific expertise to the table. <br /><br />To someone not an expert in mathematics learning, the arithmetic puzzles in our launch app, <a href="http://wuzzittrouble.com/" target="_blank">Wuzzit Trouble</a>, may look as though they are just a series of problems we generated in an essentially random fashion, following the simple rule that the numbers should get "harder" the further a player goes in the game. But that is not the case. In a mathematics learning game, the mathematics ramp is just as critical as the level design of the game, and both require a lot of expertise to get it right. <br /><br />(Interestingly, another name on our website, John Romero, is a world expert in level design – the ramping in game-play – but he joined forces with us only after we had brought out <em>Wuzzit Trouble</em>, so you will only see the results of his genius in future products we bring out.) <br /><br />Which brings me back to my promise to provide advice on how to select good learning apps. It’s probably not a foolproof method, but a quick and easy way is to check out the website of the creators, and see who they have advising them on the learning side. <br /><br />There is always the danger that some of the names are there for little more than window dressing, but the majority of education experts (indeed, experts in any domain) are not likely to lend their name to an enterprise they do not believe in. So the presence of names of distinguished mathematics educators should give you a lot of confidence in the product. <br /><br />More to the point, the absence of such names should be taken as a serious warning. Quite frankly, it is not possible to design and build an educationally sound and effective learning app without a lot of expert input. <br /><br />And I mean a lot of expert input. I bring years of my own expertise to BrainQuake, but <em>Wuzzit Trouble</em> would not have been anything like as <a href="http://wuzzittrouble.com/press.html" target="_blank">educationally successful</a> as it has, if it had just been me on the mathematics side. <br /><br />There is your quick-and-easy quality check. If you use it, you will find that list of 20,000 apps suddenly shrinks down to a significantly smaller number. Fortunately, that number is not zero. There are some great math learning apps out there. You just have to choose wisely.<br /><br />Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-11008516422631991722014-11-05T14:25:00.000-05:002014-11-05T14:45:09.662-05:00 Against Answer Getting<blockquote class="tr_bq">"Correct answers are essential... but they're part of the process, they're not the product. The product is the math the kids walk away with in their heads." —Phil Daro</blockquote><div class="MsoNormal">If you have not already watched Phil Daro's 17-minute video <a href="https://vimeo.com/79916037" target="_blank">Against Answer Getting</a>, you should do so right away. (I'll keep this post short to give you enough time to watch it in its entirety.)<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><a href="http://serpinstitute.org/index.php/people/staff/phil-daro/" target="_blank">Daro</a>, a longtime mathematics educator and leading figure in the national mathematics education community, is currently director of the San Francisco field site of <a href="http://serpinstitute.org/index.php/about/about-2/">SERP</a>, the Strategic Education Research Partnership. He was one of the mathematics educators who played a leading role in the formulation of the mathematics Common Core State Standards. (You know, one of those knowledgeable experts the StopCommonCore brigade keep claiming were not involved in CCSS development.)<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The video is full of powerful insights that the mathematics education community has accumulated over many years of research. My opening quote sums up the focus of the video. Here is another one I like:</div><blockquote class="tr_bq">"Mathematics does not break down into lesson-sized pieces." <span style="text-align: right;">—</span>Phil Daro</blockquote><div class="MsoNormal">This particular quote resonates with me. I adopted the same principle in the design of my MOOC <a href="https://www.coursera.org/course/maththink" target="_blank">Introduction to Mathematical Thinking</a>, currently about halfway through its fifth run.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Daro's focus, both in the video and in his work in general, is K-12 mathematics education. But it is very relevant to those of us in college-level mathematics education. When students come to college with a perception that mathematics is about "answer getting," we face the very uphill task of ridding them of that misleading mindset. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">True, for hundreds of years, getting answers was a key component of learning and doing mathematics. But these days, if we want answers in mathematics, we generally use one of a number of digital technologies. The job of today's mathematician (or typical user of mathematics) is problem solving. The part that requires a human mind is when the problem has a novel aspect. It was precisely to put the focus on the thinking part that I named my MOOC the way I did.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The principle requirement for being able to solve a novel problem is conceptual understanding. That is why the issues Daro raises in that video are so central to the mathematics education of the citizens of tomorrow.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The outdated mindset about the purpose of mathematics that many students bring with them when they transition from school to college is not the only problem many have to overcome. A parallel issue manifests itself when they start to learn about mathematical proofs (if they follow the mathematics path). <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">My MOOC students are currently right in the middle of that part of the course (proofs), and many are having a very hard time coming to understand what role proofs play and what (therefore) constitutes a good proof.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The dominant perception is that proofs are what mathematicians produce in order to determine mathematical truth. That, of course, is true (at least in an idealistic sense that guides mathematical progress), but as with arithmetic answer getting, it is only part of the story. And in terms of actual mathematical practice, a very small part of the story. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">As with answer getting in K-12 math, achieving a logically correct proof is a binary target (right or wrong), which make both very easy to evaluate for correctness and assign a numerical grade. (Ka-ching!)<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">But let's pause and ask ourselves how proofs work in practice. If you want to know if Fermat's Last Theorem is true, you consult a reliable source. Today, any moderately knowledgeable mathematician will tell you the answer: "Yes." Now you know. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">But what if you want to know <i>why</i>it is true. That's when you need to look at a proof. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">In terms of mathematical practice, proofs are about understanding. They are communicative devices we construct to convince ourselves and to convince others.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">In my MOOC, because I cannot assume the students have access to individualized, expert feedback on their work, I do not ask them to construct proofs. But I do present them with a range of purported proofs, some correct, others not, and ask them to evaluate them. The evaluation is in terms both of logical correctness and communicative effectiveness. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">To do this, I ask them to look at each purported proof in terms of five different factors: one logical correctness, the others focusing on communicative issues. Though the five factors are not independent variables, I ask them to treat them as such when evaluating a proof.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">This is the part of the course where those students who have had some exposure to proofs in the K-12 system tend to do worse than those who are new to proofs. They are simply not able to approach a proof other than in the "answer getting" mode of "Is it logically correct?"<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">This shows up dramatically with extremal cases. When I present them with a carefully constructed argument that is logically correct but provides no explanation, they will give it high marks across the board. But faced with an argument that is superbly articulated but has a logical flaw, they are psychologically unable to evaluate the structure of the argument. "It's wrong," they keep saying. End of story (for them).<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Of course, extremal examples are atypical, and often difficult to wrap our minds around. That's what makes them so valuable as learning devices. It's when the classroom rubber hits the road and we find ourselves using mathematical thinking in our lives or careers that it becomes important to have good communication skills.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Pick up a more advanced level mathematics book or research article and the chances are high that the arguments presented will contain errors. (Actually, the book does not have to be advanced. Euclid's <i>Elements</i> is littered with "proofs" that are not logically sound.) But if the arguments are well laid out, with adequate explanations, a suitably skilled reader can fix them as they go along<span style="text-align: right;">—</span>possibly with help from someone else. (That's definitely the case with <i>Elements</i>, though it took two thousand years before David Hilbert noticed that Euclid's own arguments left a lot of work to be done to make them genuine "proofs.")<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">It's the same in software engineering. Any useful program will have bugs. But if the code is well structured, and adequately annotated, someone else can dive in and fix it whenever a flaw manifests. A <i>good</i> computer programmer is not someone who writes error-free, working code; it is someone who writes working code that can easily be fixed or modified.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">I'll leave it as an exercise for the reader to identify the analogous issue in the natural sciences.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">If those of us in the education business want to do the best we can to prepare our students for life in the 21st century, we need to recognize that in an era when technologies provide instant answers (facts), the one ability they will need above anything else is (creative, reflective) thinking. <o:p></o:p></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-4581315717959500192014-10-07T14:21:00.001-04:002014-10-07T14:21:59.639-04:00The Straw TeacherWhen people argue for a position they hold because of political bias or some deep-rooted sense of conviction (as opposed to one arrived at by a process of reflection, weighing all sides of the issue), they often resort to straw-man tactics. This is particularly common in the U.S Math Wars, which these days are largely focused on the Common Core State Standards for mathematics.<br /><br />A particularly popular straw man – more precisely, a "straw teacher" (a term that nicely gets us out of gender issues) – is a math teacher who spends class time exclusively discussing mathematics concepts (whatever that means) and pays no attention to helping the students master any procedures.<br /><br /> I guess there may be such a teacher, somewhere, but I have to confess I have yet to meet one. Ditto for the straw teacher who says getting the right answer (if there is one) is not important. Teachers just don't do either of those.<br /><br />My colleagues who work in classroom teacher preparation do tell me that many math teachers do little else than drill on procedures (in some cases because they never set out to teach math, and don't really understand the concepts themselves), but in my walk of life I never meet them. I see the ones who became math teachers because they love mathematics and want to teach, and attend mathematics teacher conferences to exchange ideas and to learn more – which is where I meet them.<br /><br />Anyone who has a working knowledge of (1) what mathematics (really) is and (2) how the brain works knows that learning math in a useful way requires both mastery of a set of basic procedures and conceptual understanding of the mathematical notions those procedures are built on.<br /><br /> In practical terms, you need to master basic procedures in order to develop conceptual understanding, and you need conceptual understanding in order to avoid any procedural mastery being brittle and short-lived.<br /><br />So good math teaching involves both. And, for the record (yet again), both are called for in the CCSS.<br /><br />Absent the CC connection, I've written about this issue on a number of occasions before in this column. For instance:<br /><br />March 2006: <a href="http://www.maa.org/external_archive/devlin/devlin_03_06.html" target="_blank">How do we learn math?</a><br />September 2007: <a href="http://www.maa.org/external_archive/devlin/devlin_09_07.html" target="_blank">What is conceptual understanding?</a><br /><br />Both articles were written long before the Common Core was developed. They were also written when I was just starting to become more actively involved in K-12 education issues. (And before I inadvertently ignited the "repeated addition" firestorm in the summer of 2008.) But having just re-read them for the first time in many years, I still stand by what I wrote. So I won't repeat myself here.Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-42563716809689701472014-09-02T09:31:00.000-04:002014-09-02T10:45:37.588-04:00Will the Real Geometry of Nature Please Stand Up?Is fractal geometry “<strong><em>the</em></strong> geometry of nature”? I was asked this question recently in an email from someone who had watched the PBS video <a href="http://www.pbs.org/wgbh/nova/physics/hunting-hidden-dimension.html" target="_blank"><em>Hunting the Hidden Dimension</em></a> that I worked on, and appeared in, a few years ago.<br /><br />It would have been easy to simply reply “Yes,” and for many audiences I would (and have) done just that—for this was by no means the first time I had been asked that question, or others very much like it. But the context in which this recent questioner raised the issue merited a less superficial response. So I wrote back to say that there is no such thing as <strong><em>the</em></strong> geometry of nature, or more generally, <strong><em>the</em></strong> mathematics of W, where W is some real world domain.<br /><br />The strongest claim that can be made is something along the lines of “Mathematical theory T is the best mathematical description (or model) we currently have of the real world domain (or phenomenon) W.” But even then, this statement is less definitive than it might first appear: In particular, what do we mean by “best”?<br /><br />Best in terms of understanding? (If so, then understanding by whom?)<br /><br />Best in terms of building something in W? (If so, then building out of what, using what tools, and for what use?)<br /><br />Best in terms of teaching someone about W? (If so, then teaching what kind of person in terms of age, background, education, motivation, etc.?)<br /><br />Slightly edited and extended, the next few paragraphs are what I wrote back to my correspondent:<br /><br />Nature is just what it is. Mathematics provides various ways to model our perception and experience of reality. Different parts of mathematics provide different models, some better than others. Fractal geometry provides one model that seems to accord with our observations, measurements, and experiences. But so too do the cellular automata models on which Steve Wolfram bases his “<a href="https://www.wolframscience.com/" target="_blank">New Kind of Science</a>.”<br /><br />Many of us think fractal geometry does a better job than cellular automata in helping us understand the natural world by virtue of its nature, but that reflects an assumed patterns/relationship conception of what constitutes science.<br /><br />I would prefer to call Wolfram’s framework a <strong><em>computational theory</em></strong> (of the world), rather than science. But the distinction is, I think, purely one of the meaning we attach to the relevant words (particularly “science”).<br /><br />Both approaches can be said to begin by looking at how nature works, but the moment you start to create a model, you leave nature and are into the realm of human theorizing. From then on, the only available metrics are (1) degree of fit to observations and measurements, (2) degree of utility, and (3) degree to which we find the model’s assumptions reasonable.<br /><br />There is lots of slack here.<br /><br />In (1), what are we observing and measuring? (They are often entities created by those very mathematical theories, e.g. mass, length, volume, velocity, momentum, temperature, etc.)<br /><br />In (2), how do we define utility? Doing stuff, building stuff, understanding stuff, teaching stuff, or something else? (Each with the various audience/use/purpose caveats I raised earlier.)<br /><br />Then there is (3). Unless we make some initial assumptions, we cannot get a theory off the ground. And make no mistake about it, we do begin with assumptions. Not arbitrary ones, to be sure—not even close to being arbitrary. For the resulting theory to be fully accepted (as a plausible explanation or model), it has to accord to any and all the available facts, and it has to be falsifiable—it should make claims or imply conclusions that we can attempt to prove wrong.<br /><br />For instance, a mathematical theory that implied 3 = 4 (as an identity of integers) would be immediately rejected.<br /><br />What about a theory that implies 0.999… = 1.0, where those three dots indicate that the decimal series continues for ever? According to the widely accepted, standard definitions that mathematicians use to provide meaning to the concept of an infinite sequence of decimal digits, this identity is correct. Indeed, it can be proved to be correct, starting from the reasonable, plausible, and accepted basic principles (axioms) for the real number system.<br /><br />Most university math students learn about the framework within which 0.999… is indeed equal to 1.0. (Though many of the popular “proofs” you come across are not rigorous.) As a result, many mathematically educated people will state, as if it were an absolute fact of the world, that 0.999 = 1.0. But that is not true. The identity holds because we have made some assumptions about how to handle infinity. It’s easy to overlook that fact. So let me provide a further example where it may be less easy to miss an underlying assumption.<br /><br />Graduate students of mathematics are introduced to further assumptions (about handling the infinite, and various other issues), equally reasonable and useful, and in accord both with our everyday intuitions (insofar as they are relevant) and with the rest of mainstream mathematics. And on the basis of those assumptions, you can prove that<br /><br />1 + 2 + 3 + … = –1/12.<br /><br />That’s right, the sum of all the natural numbers equals –1/12.<br /><br />This result is so much in-your-face, that people whose mathematics education stopped at the undergraduate level (if they got that far) typically say it is wrong. It’s not. Just as with the 0.999… example, where we had to construct a proper meaning for an infinite decimal expansion before we could determine what its value is, so to we have to define what that infinite sum means.<br /><br />It turns out that there is an entire branch of mathematics, called analytic continuation theory, that provides us with a “natural” meaning for (in particular) that sum. And when we calculate the value using that meaning, we arrive at the answer -1/12. See <a href="http://en.wikipedia.org/wiki/1_%2B_2_%2B_3_%2B_4_%2B_%E2%8B%AF" target="_blank">this Wikipedia article</a> for a brief account.<br /><br />Incidentally, just as with the 0.999… example, you will find purported “intuitive proofs” floating around, among them <a href="https://www.youtube.com/watch?v=w-I6XTVZXww" target="_blank">this video</a> that went viral earlier this year, but those arguments too are not rigorous.<br /><br />Both frameworks, the one that yields a value for 0.999… and the one that produces a value for 1 + 2 + 3 + … , satisfy all the requirements of being reasonable, plausible, consistent with the rest of mainstream mathematics, and useful (in studies of real world phenomena, including physics). If you accept one, you really cannot reasonably deny the other. Rather, you have to accept the implications they yield, even if they at first seem counter to your expectations.<br /><br />True, neither identity accords with our experiences in the physical world, since those experiences do not involve any infinite quantities or processes. (So there is nothing to accord with!)<br /><br />One of the things surprising examples involving infinity remind us of is that mathematics is not “the true theory of the real world” (whatever that might mean). Rather, mathematical theories are mental frameworks we construct to help us make sense of the world. They survive or wither according to the degree to which they continue to accord with our real world experiences and to prove useful to us in conducting our individual and collective lives.<br /><br />To return to geometry. For most people, throughout human history the geometry of the world experienced was planar Euclidean geometry, which accords extremely well with our everyday experiences.<br /><br />But for the global air traveler (such as long distance airplane pilots), and for the astronauts in the International Space Station, spherical geometry is “<strong><em>the</em></strong> geometry.” In still other circumstances (for the most part, physics and cosmology), hyperbolic and elliptic geometries are the best frameworks.<br /><br />For the artist trying to represent three dimensions on a two-dimensional canvas (or the movie or video-game animator trying to represent three dimensions on a screen), projective geometry is the best framework.<br /><br />Picking up on my opening example, when you adopt a geometric perspective to try to understand growth in the natural world, you find that fractal geometry is the most appropriate one to hand.<br /><br />And, finally, when you adopt a geometric perspective to try to make sense of social life in today’s multi-cultural societies, you may find that higher dimensional Euclidean geometries seem to work best, as I explain in <a href="https://vimeo.com/90522211" target="_blank">this video</a> (30 minutes) taken from a talk I gave at a conference in New Mexico earlier this year. (The relevant segment starts at 3:20 and ends at 11:00.)<br /><br />The fact is, there is not just one geometry, and there is no such thing as “<strong><em>the</em></strong> geometry of W,” where W is a real world phenomenon or domain.<br /><br />Likewise for other branches of mathematics we develop and use to understand our world and to do things in our world.<br /><br />This means that, whereas, <strong><em>within mathematics</em></strong> there are “right answers,” when you apply mathematics to the world, that certainty and accuracy is only as good as the fit between the mathematics (as a conceptual framework) and the world.<br /><br />And now we are back, more or less, at the topic of my <a href="http://devlinsangle.blogspot.com/2014/08/most-math-problems-do-not-have-unique.html" target="_blank">previous <em>Devlin’s Angle</em> post</a>. It merits a second look. Given the nature of the modern world, with mathematical models playing such a major role, with major consequences (in banking, information storage, communication, transportation, national security, etc.), we should not lose track of the fact that mathematics is not the truth.<br /><br />Rather, it provides us with useful <strong><em>models</em></strong> of the world. As a result, it is a powerful and useful way of making sense of the world, and doing things in the world.<br /><br />This distinction was not particularly significant for anyone growing up in the 20th century and earlier. Back then, there was usually no danger in viewing mathematics as if it were the truth. But it is an absolutely critical distinction to keep in mind for those coming of age today.<br /><br />That New Mexico talk video I referred to a moment ago was in fact from a conference on middle school mathematics education, and was an attempt to raise awareness among middle school math teachers of the need to make their students aware of the way mathematics is used in the world they will live in and help shape, emphasizing not only mathematics’ strengths but also its limitations.<br /><br />When you think about what is at stake here, much of the current debate (largely uninformed on the opposition side) about the Common Core State Standards resembles nothing more than two elderly bald men arguing over ownership of a comb.<br /><br />In the case of the UK’s Falkland’s War of 1983, where <a href="http://en.wikiquote.org/wiki/Falklands_War" target="_blank">this analogy originated</a>, both sides appeared equally stupid. The sad aspect to the CCSS debate is that the level of ignorance (or malicious intent) on the “Stop” side forces many well-informed teachers and mathematics learning experts to devote time to the debate, lest ignorance prevail and our kids find themselves unable to survive in the world they inherit. (What the debate should focus on is how to properly implement the Standards. There be dragons, and someone needs to slay them.)<br /><br />WORTH LISTENING TO: American RadioWorks has just aired an excellent <a href="http://www.wnyc.org/story/greater-expectations-challenge-common-core/" target="_blank">radio documentary</a> about the Common Core, in which we hear from real teachers who have been using it, both in states where it has been implemented according to plan and others where the implementation has been modified.Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-43535497067099880012014-08-01T04:00:00.000-04:002014-08-01T04:00:02.236-04:00Most Math Problems Do Not Have a Unique Right AnswerOne of the most widely held misconceptions about mathematics is that a math problem has a unique correct answer.<br /><br />(Some of those who hold that view also think that there is just one correct way to get that answer. A far smaller group, to be sure, but still a worryingly large number. Still, my focus here is on the first false belief.)<br /><br />Having earned my living as a mathematician for over 40 years, I can assure you that the belief is false. In addition to my university research, I have done mathematical work for the U. S. Intelligence Community, the U.S. Army, private defense contractors, and a number of for-profit companies. In not one of those projects was I paid to find "the right answer." No one thought for one moment that there could be such a thing.<br /><br />So what is the origin of those false beliefs? It's hardly a mystery. People form that misconception because of their experience at school. In school mathematics, students are only exposed to problems that (a) are well defined, (b) have a unique correct answer, and (c) whose answer can be obtained with a few lines of calculation.<br /><br />But the only career in which a high school graduate can expect to continue to work on such problems is academic research in pure mathematics—and even then (and again speaking from many years of personal experience), cleanly specified problems that have (obtainable) "right answers" are not as common as you might think.<br /><br />Since the vast majority of students who go through school math classes do not end up as university research mathematicians, whereas many do find themselves in careers that require some mathematical ability, it's reasonable to ask why their entire school mathematics education focuses exclusively on one tiny fraction of all possible mathematics problems.<br /><br />The answer can be found by looking at the history of mathematics. Starting with the invention of numbers around 10,000 years ago, people developed mathematical methods to solve problems they faced in the world: arithmetic and algebra to use in trade and engineering, geometry and trigonometry for building and navigation, calculus for scientific research, and so forth. <br /><br />While some of that mathematics was required only by specialists (e.g. calculus), arithmetic and parts of algebra in particular were essential for everyday living. As a consequence, mathematicians wrote books from which ordinary people could learn how to calculate. From the very earliest textbooks (Babylonian tablets, Indian manuscripts, etc.), two kinds of problems were presented: algorithm ("recipes") problems that showed the steps to be carried out to do a particular kind of computation, presented without any context, and word problems, designed to help people learn how to apply a particular algorithm to solve a real world problem. Ancient and medieval textbooks had many hundreds of such problems, so that a trader (say) could find a problem almost identical in form to the one he (and back then use of mathematics was primarily a male activity) actually wanted to solve in his business. If he were lucky, all he would have to do is substitute his own numbers for those in the book's worked word problem. In other cases, the book might not provide an exact match, but by working through five or six problems that were close in form, the individual could learn how to solve his real problem.<br /><br />For the majority of people, that was enough. Life simply did not require anything more. The problems they faced in their everyday activities for which mathematics was needed were simple and routine. The mathematical word problems that today seem so unrealistic were by and large remarkably similar to the problems ordinary citizens faced every day. <br /><br />"When do I need to leave home in order to catch that train?" There wasn't an app to tell you the answer; you had to calculate it yourself. That word problem about trains leaving stations in your math class showed you how.<br /><br />Arithmetic, in particular, was an essential, basic life skill that remained so until the development of devices that automated the process in the 1960s. I am a member of the last generation for whom the question "What do I need arithmetic for?" simply did not arise. (We asked it about other parts of mathematics.)<br /><br />But that computer technology that eliminated the need for people to be good calculators led to a world in which there is a huge demand for higher order mathematical skills, starting with algebra. I wrote about this change in this column back in 1998, in a piece titled "<a href="https://www.maa.org/external_archive/devlin/devlin_3_98.html" target="_blank">Forget 'Back to Basics.' It's Time for 'Forward to (the New) Basics.</a><u>'"</u> Looking back at what I wrote then, I am amazed at just how much things have changed in the intervening 16 years. In September of that year, Google was founded, and the Web became a dominant force in our lives and our work.<br /><br />Today, we have instant access to vast amounts of information and to unlimited computing power. Both are now utilities, much like water and electricity. And that has led to a revolution in the mathematics ordinary citizens need in order to lead a fulfilling, productive life. In a world where procedural (i.e., algorithmic) mathematics is available at the push of a button, the need has shifted to what I and others have been calling mathematical thinking. <br /><br />I wrote about this in my <a href="http://devlinsangle.blogspot.com/2012/08/what-is-mathematical-thinking.html" target="_blank">September 2012 <i>Devlin's Angle</i></a>. Broadly speaking, mathematical thinking is a way of approaching problems that is based on classical mathematics, but takes account of the fact that computation (both numeric and symbolic) can be readily done by machines.<br /><br />In practical terms, what this means is that people can now focus all their attention on real-world problems in the form they are encountered. Knowing how to solve an equation is no longer a valuable human ability; what matters now is formulating the equation to solve that problem in the first place, and then taking the result of the machine solution to the equation and making use of it.<br /><br />In the 1960s, we got used to the fact that the arithmetic part of solving a mathematical problem could be done by machines. Now we are in a world where almost all the procedural mathematics can be done by machines.<br /><br />Of course, this does not mean we should stop teaching procedural mathematics to the next generation, any more than the introduction of pocket calculators meant we should stop teaching arithmetic. But in both cases, the reason for teaching changes, and with it the way we should teach it. The purpose shifts from mastering procedures—something that was necessary only when there were no machines to do that part—to understanding the concepts sufficiently well to make good use of those machines.<br /><br />Though this change in emphasis has been underway for some years now, it did not garner much attention in the United States until the rollout of the Common Core State Standards, which are very much geared towards the mathematical thinking needs of the 21st century. The degree to which many parents were shortsighted by the shift was made clear when some of them took to social media to complain about the kinds of homework questions their children were being asked to do. While some of those questions were truly, truly awful, others garnering a lot of critical SM comments were actually extremely good.<br /><br />What was particularly ironic was that many parents, faced with being unable to assist their child with elementary grade arithmetic homework, did not draw the obvious conclusion: "Gee, if I cannot understand something as basic as integer arithmetic—however it is done—there must have been something really lacking in my own education." Instead, they jumped to the totally off-the-wall conclusion that the current educational system must be wrong.<br /><br />That's like waking up in the morning to find your car won't start and saying, "Oh dear, the laws of physics don't work." The smart person says, "I need to replace the battery."<br /><br />I'll tell you something. I was taught math the "old-fashioned way" too, and some of those student arithmetic worksheets were new to me when I first saw them. But regardless of any views I might have as to how it is best taught in today's world, it didn't take a lot of effort to figure out what those kids were doing on those worksheets posted on Facebook. It was just whole number arithmetic for heavens sake! Anyone who understands the basic ideas of whole number arithmetic can figure it out.<br /><br />It was not my training as a professional mathematician that helped me here. It was the simple fact that I understand whole number arithmetic, something that goes back to my early childhood, when I did not even know there was such a thing as a professional mathematician, let alone aspire to be one. Unfortunately, many Americans were never taught to understand arithmetic, they were just trained to execute procedures. It's not their kids who are being short-changed. They—the parents—were!<br /><br />Breezing into this fray is University of Wisconsin mathematics professor Jordan Ellenberg, with his new book <a href="http://www.amazon.com/How-Not-Be-Wrong-Mathematical/dp/1594205221/ref=sr_1_1?ie=UTF8&qid=1406591086&sr=8-1&keywords=how+not+to+be+wrong" target="_blank"><i>How Not To Be Wrong</i></a>. I knew I would find a kindred spirit when I read the book's subtitle: “The Power of Mathematical Thinking.” With a <a href="https://www.coursera.org/course/maththink">Stanford MOOC</a> and an associated <a href="http://www.amazon.com/Introduction-Mathematical-Thinking-Keith-Devlin/dp/0615653634/ref=sr_1_5?ie=UTF8&qid=1342652878&sr=8-5&keywords=devlin+mathematical+thinking" target="_blank">textbook</a> both called <i>Introduction to Mathematical Thinking</i>, how could I not?<br /><br />Ellenberg's title is superb. In one fell swoop, it casts aside that old misconception that mathematics provides "right answers," replacing it with the far more accurate description that it is a great way to stop you being wrong. For, like me, he focuses not on the internal activities of pure mathematics, rather on how mathematics is used in today's real world.<br /><br />To be sure, also like me, Ellenberg has devoted a lot of his career to working in pure mathematics, so he loves searching for those "right answers," and he enjoys the subject in its own terms. We both know that there are eternal truths within mathematics (a better term would be "tautologies") and have experienced the thrill of going after them. But we both realize that what we do as pure mathematicians is a very specialist pursuit. The society that supports us when we do that does so largely because of the payoff in terms of the benefits that emerge when mathematical thinking is applied to real world problems.<br /><br />Ellenberg's book is chock full of examples of those benefits, from many walks of life, presented with a delightfully light touch. He grabs the reader's attention with his very first example, taken from the Second World War. The U. S. military chiefs wanted to reduce the number of warplanes that were being shot down. The obvious solution was to add more armor to protect them. But armor adds weight, which limits the distances that can be flown and the duration of the mission, as well as increasing the production cost. So the question was, where is the most effective place to put that extra protection? <br /><br />To answer this question, the chiefs brought in a team of mathematicians to analyze the evidence and determine what parts of the aircraft were most likely to be hit. They examined the fuselages of all the damaged planes that had flown back after being hit to see where the most damage was. It turned out that the engines had an average of 1.11 bullet holes per square foot, the fuel system had 1.55, the fuselages 1.73, and the rest of the plane 1.8. <br /><br />So where was the optimal place to add extra armor? According to the data, the fuselages took a lot of hits, while engines suffered the least damage. So an obvious suggestion was to add armor to the fuselages. But that was not what the mathematicians suggested. Their solution was to add the armor to the engines, the part that had fewer hits when the planes got back.<br /><br />And they were right. I'll leave you to figure out why that is the best solution. It's a great example of mathematical thinking. After you have convinced yourself why adding armor to the engines was the best strategy, you should buy a copy of Ellenberg's book and gain some understanding of just what mathematical thinking is, and why it is a crucial ability in today's world. <br /><br />(My own book on mathematical thinking is more of a "how to" guide, as is my MOOC. Another, excellent book on mathematical thinking, that is somewhere between Ellenberg's and mine, is Burger and Starbird's <a href="http://www.amazon.com/5-Elements-Effective-Thinking-ebook/dp/B008JUVDUE/ref=sr_1_3?ie=UTF8&qid=1406632051&sr=8-3&keywords=starbird+michael" target="_blank"><i>The 5 Elements of Effective Thinking</i></a>.)<br /><br />Finally, and to some extent switching gears (and definitely switching media), I want to draw your attention to a new video game, <a href="http://wewanttoknow.com/elements/" target="_blank">DragonBox Elements</a>, by the Norwegian-based educational technology company WeWantToKnow. The company made a splash with its first game, <a href="http://wewanttoknow.com/algebra/" target="_blank">DragonBox (Algebra)</a> a couple of years ago.<br /><br />Unlike my own work in educational videogames, through my company <a href="http://brainquake.com/" target="_blank">BrainQuake</a>, which is very strongly focused on real-world mathematical thinking, the DragonBox folks are seeking to enhance and strengthen school mathematics.<br /><br />When I first played the new Elements game, I was initially confused, since I approached it with a <a href="http://www.keycurriculum.com/" target="_blank">Geometer's Sketchpad</a> expectation. But Elements is not a geometry construction/exploration tool. The focus is on the importance of providing justification for steps in a proof. Knowing why something is true. And that is not only a key feature of GOFM (“Good Old Fashioned Math”), as was taught for two thousand years, it's one of the aspects of mathematics that is characteristic of mathematical thinking (as used in the real world). Euclid, the author of the first <i>Elements</i> (the book), would surely have approved.<br /><br />The modern world has not made GOFM redundant. What has changed, and drastically, is the way GOFM fits in with the rest of human activities. Unless you are going to make a career for yourself in pure mathematics research, GOFM today is simply an amazingly powerful tool for acquiring one of the most important cognitive capacities in the 21st century: mathematical thinking.<br /><br />In today's world, most of the important problems are complex and multi-faceted. There are few right answers. As Ellenberg demonstrates, mathematical thinking can help you choose better answers—and avoid being wrong.Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com3tag:blogger.com,1999:blog-2516188730140164076.post-41674229614180686672014-07-01T12:31:00.001-04:002014-07-01T13:04:50.095-04:00The Power of Dots<div class="separator" style="clear: both; text-align: center;"><a href="http://2.bp.blogspot.com/-tsiADZYB4hs/U7LfEeFMotI/AAAAAAAAJ14/DgOWU4KVhC8/s1600/Morass.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://2.bp.blogspot.com/-tsiADZYB4hs/U7LfEeFMotI/AAAAAAAAJ14/DgOWU4KVhC8/s1600/Morass.jpg" height="240" width="320" /></a></div><div><br /></div>On June 29, the <i>New York Times</i> ran <a href="http://www.nytimes.com/2014/06/30/us/math-under-common-core-has-even-parents-stumbling.html?emc=edit_tnt_20140629&eml_thmb=1&nlid=4832777&tntemail0=y&_r=1" target="_blank">a story</a> about the Common Core Mathematics Standards. If ever you wanted proof of the dismal mathematics education most Americans have been provided, you will find it in the story’s “human interest lede,” which described one mother’s response to seeing her daughter’s homework. By taking the daughter out of school to teach her herself “the old fashioned way” she herself had been subjected to, this well-meaning parent was ensuring that, as had clearly been the case for the mother, the daughter too would not be exposed to real mathematical thinking—the kind that in today’s world is a key to the most attractive jobs. Instead she would be subjected to the same, dreary, rote-skills-drills inflicted on previous generations—a process designed to train people for routine work in the pre-computer era, but so hopelessly inadequate for the 21st century that parents are un-equipped to figure out for themselves the simple (albeit unfamiliar) math homework their children are assigned.<br /><br />Surely, if mathematics education should achieve one thing, it is develop the ability to figure things out for yourself. We’re not talking the Riemann Hypothesis here; the focus is basic school arithmetic, for heaven’s sake.<br /><br />To continue with the <i>Times</i> article, arrays of dots seemed to figure large in this parent’s dislike of the Common Core. She felt it was pointless to spend time drawing and staring at arrays of dots.<br /><br />True, it would be possible—and I am sure it happens—to generate tedious, and largely pointless, “busywork” exercises involving drawing arrays of dots. But the image of a Common Core math worksheet the <i>Times</i> chose to illustrate its story showed a very sensible, and deep use of dot diagrams, to understand structure in arithmetic. Much like the (extremely deep) dot array at the top of this article, which I’ll come to in a moment.<br /><br />To the girl’s parent, mathematics is about numbers, but that’s just a surface feature. It’s really about structure. And throughout the ages, mathematicians have used the most simple symbols possible to bring out and understand that structure: namely, dots and lines.<br /><br />The <i>Times</i>’ parent, so dismissive of time spent drawing and reflecting on dot diagrams, would, I am sure, think it a waste of time to devote any effort trying to make sense of the dot diagram I used to open this post. She would, I have no doubt, find it incomprehensible that an individual with a freshly-minted Ph.D. in mathematics would spend many months—at taxpayers’ expense—staring day-after-day at either that one diagram, or seemingly minor variations he would start each day by sketching out on a sheet of paper in front of him.<br /><br />Well, I am that mathematician. That diagram helped me understand the framework that would be required to specify an infinite mathematical object of the third order of infinitude (aleph-2) by means of a family of infinite mathematical objects of the first order of infinitude (aleph-0). The top line of dots represents an increasing tower of objects that come together to form the desired aleph-2 object, and each of the lower lines of dots represent shorter towers of aleph-0 objects. In the 1970s, a number of us used those dot diagrams to solve mathematical problems that just a few years earlier had seemed impossible.<br /><br />That particular kind of dot diagram was invented by a close senior colleague (and mentor) of mine, Professor Ronald Jensen, who called it a “morass.” He chose the name wisely, since the structure represented by those dots was extremely complex and intricate. <br /><br />In contrast, the simple, rectangular array implicitly referred to in the <i>New York Times</i> article is used to help learners understand the much simpler (but still deep, and far more important to society) structure of numbers and the basic operations of arithmetic, as was well explained in a subsequent <a href="http://talkingmathwithkids.com/2014/06/30/dots/" target="_blank">blog post</a> by mathematics education specialist Christopher Danielson. The fact is, dot diagrams are powerful, for learners and world experts alike. <br /><br />The problem facing parents (and many teachers) today, is that the present student generation is the one that, for the first time in history, is having to learn the mathematics the professionals use—what I and many other pros have started to call “mathematical thinking” in order to distinguish it from the procedural skills so important in past times.<br /><br />The reason for that is that in the world today’s students will graduate into, computation is as plentiful as water or electricity. The smartphone we carry around with us is much faster, and more accurate, in carrying out mathematical procedures than any human. <br /><br />In a single generation, society’s need for mathematical mastery has gone from procedural computation, to being able to make effective and reliable use of an effectively unlimited amount of automated computation. To put it bluntly, mastery of computational skills is no longer a marketable asset. The ability to make good use of computational power is where it’s at in math today.<br /><br />For almost all the three thousand years of mathematical development, the focus in mathematics was calculation (numerical, symbolic, or geometric). Learning mathematics meant learning how to perform those calculations, which boiled down to achieving mastery of various procedures. Mastery of any one procedure could be achieved by rote learning—doing many examples, all essentially the same—leaving the only truly creative mental task that of recognition of which procedure to apply to solve which problem.<br /><br />Numerical and symbolic calculation (arithmetic and algebra) are so simple and routine that we can program computers to do it for us. That is possible because calculation is essentially trivial. Perceiving and understanding structure, on the other hand, is something that (at least at the present time) requires human insight. It is not trivial and it is difficult. Dot diagrams can help us come to terms with that difficulty.<br /><br />When movie director Gus Van Sant was faced with introducing the lead character, Will Hunting (played by Matt Damon) in the hit 1997 film <i>Good Will Hunting</i>, establishing in one shot that the hero was an uneducated (actually, self-educated) mathematical genius, the first encounter we had with Will showed him drawing a dot diagram on a blackboard in an MIT corridor.<br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="http://2.bp.blogspot.com/-yJFoRYfemaY/U7LfMQqs1TI/AAAAAAAAJ2E/Y7B_fUGac38/s1600/Good_Will_Hunting.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em; text-align: center;"><img border="0" src="http://2.bp.blogspot.com/-yJFoRYfemaY/U7LfMQqs1TI/AAAAAAAAJ2E/Y7B_fUGac38/s1600/Good_Will_Hunting.jpg" height="180" width="320" /></a></div><br />You can be sure that when an experienced movie director like Gus Van Sant selects an establishing shot for the lead character, he does so with considerable care, on the advice of an expert. By showing Will writing a network of dots on a blackboard, Van Sant was right on the button in terms of portraying the kind of thing that professional mathematicians do all the time. <br /><br />The one bit of license Van Sant took was that the diagram we saw Matt Damon writing was not the solution to a problem that had taken an MIT math professor two years to solve. (Unless MIT math professors are a lot less smart than we are led to believe!) It was a real solution to a real math problem, all right. I am pretty sure it was chosen because it fitted nicely on one blackboard and looked good on the screen. It absolutely conveyed the kind of (dotty) activity that mathematicians do all the time—the kind of (dotty) thing I did in my early post-Ph.D. years when I was working with Prof Jensen’s morasses.<br /><br />But it’s actually a problem that anyone who has learned how to think mathematically should be able to solve in at most a few hours. Numberphile has an excellent <a href="http://www.youtube.com/watch?v=iW_LkYiuTKE" target="_blank">video</a> explaining the problem.<br /><br />So, <i>New York Times</i> story parent, I hope you reconsider your decision to take your daughter out of school to teach her the way you were taught. The kind of mathematics you were taught was indeed required in times past. But not any more. The world has changed dramatically as far as mathematics is concerned. As with many other aspects of our lives, we have built machines to handle the more routine, procedural stuff, thereby putting a premium on the one thing where humans vastly outperform computers: creative thinking. <br /><br />Those dot diagrams are all about creative thinking. A computer can understand numbers, and process millions of them faster than a human can write just one. But it cannot make sense of those dot diagrams. Because it does not know what any particular array of dots means! And it has no way to figure it out. (Unless a human tells it.)<br /><br />Next month I’ll look further into the distinction between old-style procedural mathematics and the 21st-century need for mathematical thinking. In particular, I’ll look at an excellent recent <a href="http://www.amazon.com/How-Not-Be-Wrong-Mathematical/dp/1594205221/ref=sr_1_1?ie=UTF8&qid=1404226390&sr=8-1&keywords=how+not+to+be+wrong" target="_blank">book</a>, Jordan Ellenberg’s <i>How Not to be Wrong</i>. <br /><br />The book’s title is significant, since it recognizes that the vast majority of real-world mathematical problems do not have a unique right answer, and that the real power of mathematical thinking is making sure you are not wrong. (The book’s subtitle is “The power of mathematical thinking.”)<br /><br />I’ll also look at a new mathematics video game that also focuses on mathematical thinking, this time, school-room Euclidean geometry. It’s called <a href="http://wewanttoknow.com/elements/" target="_blank">DragonBox Elements</a>.<br /><br />You might want to check out both.Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com9tag:blogger.com,1999:blog-2516188730140164076.post-58098597143630895432014-06-01T05:00:00.000-04:002014-06-02T07:38:35.596-04:00Déjà vu all over again: Fibonacci and Steve Jobs — Part 2This month’s column is the second of a two-part video presentation of a public address I gave recently at Princeton, where I have been spending this semester as a Visiting Professor.<br /><br />The talk was based on my 2011 e-book <a href="http://www.amazon.com/Leonardo-Steve-Genius-Market-ebook/dp/B005BRR2TY/ref=sr_1_1?s=digital-text&ie=UTF8&qid=1310688753&sr=1-1" target="_blank"><i>Leonardo and Steve</i></a>, which itself was a supplement to my print book <a href="http://www.amazon.com/Man-Numbers-Fibonaccis-Arithmetic-Revolution/dp/0802778127/ref=sr_1_1?ie=UTF8&qid=1306990867&sr=8-1" target="_blank"><i>The Man of Numbers</i></a>, published the same year.<br /><br />Both the e-book and my presentation show how Jobs’s introduction of the Macintosh computer in 1984 was an almost exact replay of Leonardo of Pisa’s (Fibonacci) 13th Century introduction to Europe of Hindu-Arabic arithmetic.<br /><br /><a href="http://devlinsangle.blogspot.com/2014/05/deja-vu-all-over-again-fibonacci-and.html" target="_blank">Part 1 appeared last month</a>.<br /><div><div style="text-align: center;"><br /></div></div><div style="text-align: center;"><iframe allowfullscreen="" frameborder="0" height="281" mozallowfullscreen="" src="//player.vimeo.com/video/93532834" webkitallowfullscreen="" width="500"></iframe></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-81428934455161938942014-05-01T09:09:00.000-04:002014-06-02T07:39:23.215-04:00Déjà vu all over again: Fibonacci and Steve Jobs<div class="MsoNormal">This month’s column is the first of a two-part video presentation of a public address I gave recently at Princeton, where I have been spending this semester as a Visiting Professor.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The talk was based on my 2011 e-book <a href="http://www.amazon.com/Leonardo-Steve-Genius-Market-ebook/dp/B005BRR2TY/ref=sr_1_1?s=digital-text&ie=UTF8&qid=1310688753&sr=1-1" target="_blank"><i>Leonardo and Steve</i></a>, which itself was a supplement to my print book <a href="http://www.amazon.com/Man-Numbers-Fibonaccis-Arithmetic-Revolution/dp/0802778127/ref=sr_1_1?ie=UTF8&qid=1306990867&sr=8-1" target="_blank"><i>The Man of Numbers</i></a>, published the same year.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><div style="text-align: left;">Both the e-book and my presentation show how Jobs’s introduction of the Macintosh computer in 1984 was an almost exact replay of Leonardo of Pisa’s (Fibonacci's) 13<sup>th</sup> Century introduction to Europe of Hindu-Arabic arithmetic.<o:p></o:p></div></div><div class="MsoNormal"><div style="text-align: center;"><br /></div></div><div style="text-align: center;"><iframe allowfullscreen="" frameborder="1" height="281" mozallowfullscreen="" src="//player.vimeo.com/video/93390473" style="border: 1px solid black; padding: 1px;" webkitallowfullscreen="" width="500"></iframe></div><div style="text-align: center;"><br /></div><div class="MsoNormal"><a href="http://devlinsangle.blogspot.com/2014/06/deja-vu-all-over-again-fibonacci-and.html" target="_blank">Part 2 will appear next month</a>.<o:p></o:p></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com1tag:blogger.com,1999:blog-2516188730140164076.post-77001851086899909922014-04-01T01:00:00.000-04:002014-04-01T09:11:06.828-04:00What good is math and why do we teach it?This month’s column comes in lecture format. It’s a narrated videostream of the presentation file that accompanied the featured address I made recently at the <a href="http://msm2014.sched.org/directory/speakers#.Uzlti9zMTmY" target="_blank">MidSchoolMath National Conference</a>, held in Santa Fe, NM, on March 27-29. It lasts just under 30 minutes, including two embedded videos.<br /><br />In the talk, I step back from the (now largely metaphorical) blackboard and take a broader look at why we and our students are there is the first place.<br /><div style="text-align: center;"><br /></div><div style="text-align: center;"><iframe allowfullscreen="" frameborder="0" height="281" mozallowfullscreen="" src="//player.vimeo.com/video/90522211" webkitallowfullscreen="" width="500"></iframe> </div><br /><a href="https://vimeo.com/90522211" target="_blank">Download the video here</a>.Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-73606115757450595212014-03-01T01:00:00.000-05:002014-03-01T01:00:09.135-05:00How Mountain Biking Can Provide the Key to the Eureka Moment<div class="MsoNormal"><i>Because this blog post covers both mountain biking and proving theorems, it is being simultaneously published in Devlin’s more wide ranging blog <a href="http://profkeithdevlin.org/">profkeithdevlin.org</a>. </i></div><div class="MsoNormal"><div style="text-align: center;"><br /></div></div><div class="MsoNormal"><div style="text-align: center;"><iframe allowfullscreen="" frameborder="0" height="315" src="//www.youtube.com/embed/wUUlkpSOIcg" width="560"></iframe></div><div class="MsoNormal"><div style="text-align: center;"><br /></div></div><div class="MsoNormal">In my <a href="http://devlinsangle.blogspot.com/2014/02/want-to-learn-how-to-prove-theorem-go.html" target="_blank">post last month</a>, I described my efforts to ride a particularly difficult stretch of a local mountain bike trail in the hills just west of Palo Alto. As promised, I will now draw a number of conclusions for solving difficult mathematical problems. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Most of them will be familiar to anyone who has read George Polya’s classic book <i><a href="http://www.amazon.com/How-To-Solve-It-Mathematical/dp/4871878309/ref=sr_1_1?ie=UTF8&qid=1393493951&sr=8-1&keywords=george+polya" target="_blank">How to Solve It</a></i>. But my main conclusion may come as a surprise unless you have watched movies such as <i>Top Gun</i>or <i>Field of Dreams</i>, or if you follow professional sports at the Olympic level.</div><div class="MsoNormal"><o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Here goes, step-by-step, or rather pedal-stroke-by-pedal-stroke. (I am assuming you have recently read my last post.)<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">BIKE: Though bikers with extremely strong leg muscles can make the Alpine Road ByPass Trail ascent by brute force, I can't. So my first step, spread over several rides, was to break the main problem—get up an insanely steep, root strewn, loose-dirt climb—into smaller, simpler problems, and solve those one at a time. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">MATH: <span style="color: #343434; mso-bidi-font-family: "Lucida Grande";">Breaking a large problem into a series of smaller ones is a technique all mathematicians learn early in their careers. </span>Those subproblems may still be hard and require considerable effort and several attempts, but in many cases you find you can make progress on at least some of them. The trick is to make each subproblem sufficiently small that it requires just one idea or one technique to solve it.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">In particular, when you break the overall problem down sufficiently, you usually find that each smaller subproblem resembles another problem you, or someone else, has already solved.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">When you have managed to solve the subproblems, you are left with the task of assembling all those subproblem solutions into a single whole. This is frequently not easy, and in many cases turns out to be a much harder challenge in its own right than any of the subproblem solutions, perhaps requiring modification to the subproblems or to the method you used to solve them.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">BIKE: Sometimes there are several different lines you can follow to overcome a particular obstacle, starting and ending at the same positions but requiring different combinations of skills, strengths, and agility. (See my description last month of how I managed to negotiate the steepest section and avoid being thrown off course—or off the bike—by that troublesome tree-root nipple.)<br /><o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">MATH: Each subproblem takes you from a particular starting point to a particular end-point, but there may be several different approaches to accomplish that subtask. In many cases, other mathematicians have solved similar problems and you can copy their approach.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">BIKE: Sometimes, the approach you adopt to get you past one obstacle leaves you unable to negotiate the next, and you have to find a different way to handle the first one.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">MATH: Ditto.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">BIKE: Eventually, perhaps after many attempts, you figure out how to negotiate each individual segment of the climb. Getting to this stage is, I think, a bit harder in mountain biking than in math. With a math problem, you usually can work on each subproblem one at a time, in any order. In mountain biking, because of the need to maintain forward (i.e., upward) momentum, you have to build your overall solution up in a cumulative fashion—vertically!<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">But the distinction is not as great as might first appear. In both cases, the step from having solved each individual subproblem in isolation to finding a solution for the overall problem, is a mysterious one that perhaps cannot be appreciated by someone who has not experienced it. This is where things get interesting.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Having had the experience of solving difficult (for me) problems in both mathematics and mountain biking, I see considerable similarities between the two. <i>In both cases, the subconscious mind plays a major role</i>—which is, I presume, why they seem mysterious. This is where this two-part blog post is heading.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">BIKE: I ended my previous post by promising to <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><blockquote class="tr_bq">"look at the role of the subconscious in being able to put together a series of mastered steps in order to solve a big problem. For a very curious thing happened after I took the photos to illustrate this post. I walked back down to collect my bike from…where I'd left it, and rode up to continue my ride.</blockquote><blockquote class="tr_bq"><i>It took me four attempts to complete that initial climb!</i></blockquote><blockquote class="tr_bq">And therein lies one of the biggest secrets of being able to solve a difficult math problem."</blockquote></div><div class="MsoNormal"><br /></div><div class="MsoNormal">BOTH: How does the human mind make a breakthrough? How are we able to do something that we have not only never done before, but failed many times in attempts to do so? And why does the breakthrough always seem to occur when we are <i>not consciously trying to solve the problem?</i><o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The first thing to note is that we never experience the process of making that breakthrough. Rather, what we experience, i.e., what we are conscious of, is <i>having just made</i>the breakthrough! <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The sensation we have is a combined one of both elation <i>and surprise</i>. Followed almost immediately by a feeling that <i>it wasn’t so difficult after all!</i><o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">What are we to make of this strange process?<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Clearly, I cannot provide a definitive, concrete answer to that question. No one can. <a href="https://www.youtube.com/watch?v=wUUlkpSOIcg" target="_blank">It’s a mystery</a>. But it is possible to make a number of relevant observations, together with some reasonable, informed speculations. (What follows is a continuation of sorts of the thread I developed in my 2000 book <i><a href="http://www.amazon.com/Math-Gene-Mathematical-Thinking-Evolved-ebook/dp/B0054QML1G/ref=sr_1_1?ie=UTF8&qid=1393493643&sr=8-1&keywords=the+math+gene" target="_blank">The Math Gene</a></i>.)</div><div class="MsoNormal"><br /></div><div class="MsoNormal">The first observation is that the human brain is a result of millions of years of survival-driven, natural selection. That made it supremely efficient at (rapidly) solving problems that threaten survival. Most of that survival activity is handled by a small, walnut-shaped area of the brain called the amygdala, working in close conjunction with the body’s nervous system and motor control system.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">In contrast to the speed at which our amydala operates, the much more recently developed neo-cortex that supports our conscious thought, our speech, and our “rational reasoning,” functions at what is comparatively glacial speed, following well developed channels of mental activity—channels that can be built up by repetitive training.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Because we have conscious access to our neo-cortical thought processes, we tend to regard them as “logical,” often dismissing the actions of the amygdala as providing (“mere,” “animal-like”) “instinctive reactions.” But that misses the point that, because that “instinctive reaction organ” has evolved to ensure its owner’s survival in a highly complex and ever changing environment, it does in fact operate in an extremely logical fashion, honed by generations of natural selection pressure to be in sync with its owner’s environment.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Which leads me to this.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Do you want to identify that part of the brain that makes major scientific (and mountain biking) breakthroughs? <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">I nominate the amygdala—the “reptilian brain” as it is sometimes called to reflect its evolutionary origin.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">I should acknowledge that I am not the first person to make this suggestion. Well, for mathematical breakthroughs, maybe I am. But in sports and the creative arts, it has long been recognized that the key to truly great performance is to essentially shut down the neo-cortex and let the subconscious activities of the amygdala take over.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Taking this as a working hypothesis for mathematical (or mountain biking) problem solving, we can readily see why those moments of great breakthrough come only after a long period of preparation, where we keep working away—in conscious fashion—at trying to solve the problem or perform the action, seemingly without making any progress. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">We can see too why, when the breakthrough (or the great performance) comes, it does so instantly and surprisingly, <i>when we are not actively trying to achieve the goal</i>, leaving our conscious selves as mere after-the-fact observers of the outcome.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">For what that long period of struggle does is build a cognitive environment in which our reptilian brain—living inside and being connected to all of that deliberate, conscious activity the whole time—can make the key connections required to put everything together. In other words, investing all of that time and effort in that initial struggle raises the internal, cognitive stakes to a level where the amygdala can do its stuff.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Okay, I’ve been playing fast and loose with the metaphors and the anthropomorphization here. We’re really talking about biological systems, simply operating the way natural selection equipped them. But my goal is not to put together a scientific analysis, rather to try to figure out how to improve our ability to solve novel problems. My primary aim is not to be “right” (though knowledge and insight are always nice to have), but to be able to improve performance.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Let’s return to that tricky stretch of the ByPass section on the Alpine Road trail. What am I consciously focusing on when I make a successful ascent? <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">BIKE: If you have read my earlier account, you will know that the difficult section comes in three parts. What I do is this. As I approach each segment, I consciously think about, and fix my eyes on, the end-point of that segment—where I will be after I have negotiated the difficulties on the way. And I keep my eyes and attention focused on that goal-point until I reach it. For the whole of the maneuver, I have no conscious awareness of the actual ground I am cycling over, or of my bike. It’s total focus on where I want to end up, and nothing else. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">So who—or what—is controlling the bike? The <a href="http://en.wikipedia.org/wiki/Bicycle_and_motorcycle_dynamics" target="_blank">mathematical control problem</a> involved in getting a person-on-a-bike up a steep, irregular, dirt trail is far greater than that required to auto-fly a jet fighter. The calculations and the speed with which they would have to be performed are orders of magnitude beyond the capability of the relatively slow neuronal firings in the neocortex. There is only one organ we know of that could perform this task. And that’s the amygdala, working in conjunction with the nervous system and the body’s motor control mechanism in a super-fast constant feedback loop. All the neo-cortex and its conscious thought has to do is avoid getting in the way!</div><div class="MsoNormal"><o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">These days, in the case of Alpine Road, now I have “solved” the problem, the only things my conscious neo-cortex has to do on each occasion are switching my focus from the goal of one segment to the goal of the next. If anything interferes with my attention at one of those key transition moments, my climb is over—and I stop or fall. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">What used to be the hard parts are now “done for me” by unconscious circuits in my brain.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">MATH: In my case at least, what I just wrote about mountain biking accords perfectly with my experiences in making (personal) mathematical problem-solving breakthroughs. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">It is by stepping back from trying to solve the problem <i>by putting together everything I know and have learned in my attempts</i>, and instead simply focusing on the problem itself—what it is I am trying to show—that I suddenly find that I have the solution.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">It’s not that I arrive at the solution when I am not thinking about the problem. Some mathematicians have expressed their breakthrough moments that way, but I strongly suspect that is not totally true. When a mathematician has been trying to solve a problem for some months or years, that problem is always with them. It becomes part of their existence. There is not a single waking moment when that problem is not “on their mind.” <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">What they mean, I believe, and what I am sure is the case for me, is that the breakthrough comes when the problem is not the focus of our thoughts. We really are thinking about something else, often some mundane detail of life, or enjoying a marvelous view. (Google “Stephen Smale beaches of Rio” for a famous example.)<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">This thesis does, of course, explain why the process of walking up the ByPass Trail and taking photographs of all the tricky points made it impossible for me to complete the climb. True, I did succeed at the fourth attempt. But I am sure that was not because the first three were “practice.” Heavens, I’d long ago mastered the maneuvers required. It was because it took three failed attempts before I managed to erase the effects of focusing on the details to capture those images.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The same is true, I suggest, for solving a difficult mathematical problem. All of those techniques Polya describes in his book, some of which I list above, are essential to prepare the way for solving the problem. But the solution will come only when you forget about all those details, and just focus on the prize.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">This may seem a wild suggestion, but in some respects it may not be entirely new. There is much in common between what I described above and the highly successful <a href="http://legacyrlmoore.org/reference/mahavier1.html" target="_blank">teaching method</a> of R. L. Moore. For sure you have to do a fair amount of translation from his language to mine, but Moore used to demand that his students not clutter their minds by learning stuff, rather took each problem as it came and then try to solve it by pure reasoning, not giving up until they found the solution.</div><div class="MsoNormal"><o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">In terms of training future mathematicians, what these considerations imply, of course, is that there is mileage to be had from adopting some of the techniques used by coaches and instructors to produce great performances in sports, in the arts, in the military, and in chess. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Sweating the small stuff will make you good. But if you want to be great, you have to go beyond that—you have to forget the small stuff and keep your eye on the prize. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">And if you are successful, be sure to give full credit for that Fields Medal or that AMS Prize where it is rightly due: dedicate it to your amygdala. It will deserve it.<o:p></o:p></div></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com4tag:blogger.com,1999:blog-2516188730140164076.post-7816673223673752482014-02-01T01:00:00.000-05:002014-03-04T12:53:25.340-05:00Want to learn how to prove a theorem? Go for a mountain bike ride<div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="font-family: inherit;"><i><span style="color: #262626;">Because this blogpost covers both mountain biking and proving theorems, it is being simultaneously published in Devlin’s more wide ranging blog <a href="http://profkeithdevlin.org/" target="_blank">profkeithdevlin.org</a>.</span></i><span style="color: #262626;"><o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Mountain biking is big in the San Francisco Bay Area, where I live. (In its present day form, using specially built bicycles with suspension, the sport/pastime was invented a few miles north in Marin County in the late 1970s.) Though there are hundreds of trails in the open space preserves that spread over the hills to the west of Stanford, there are just a handful of access trails that allow you to start and finish your ride in Palo Alto. Of those, by far the most popular is Alpine Road.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">My mountain biking buddies and I ascend Alpine Road roughly once a week in the mountain biking season (which in California is usually around nine or ten months long). In this post, I'll describe my own long struggle, stretching over many months, to master one particularly difficult stretch of the climb, where many riders get off and walk their bikes.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">[SPOILER: <i>If your interest in mathematics is not matched by an obsession with bike riding, bear with me. My entire account is actually about how to set about solving a difficult math problem, particularly proving a theorem. I'll draw the two threads together in a subsequent post, since it will take me into consideration of how the brain works when it does mathematics. For now, I'll leave the drawing of those conclusions as an exercise for the reader! So when you read mountain biking, think math.</i>]<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Alpine Road used to take cars all the way from Palo Alto to Skyline Boulevard at the summit of the Coastal Range, but the upper part fell into disrepair in the late 1960s, and the two-and-a-half-mile stretch from just west of Portola Valley to where it meets the paved Page Mill Road just short of Skyline is now a dirt trail, much frequented by hikers and mountain bikers.<o:p></o:p></span></span></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody><tr><td style="text-align: center;"><a href="http://3.bp.blogspot.com/-ryAjI2oBZUo/UuaurMnIp5I/AAAAAAAAJUA/LzvbK0fuLsQ/s1600/AD1.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://3.bp.blogspot.com/-ryAjI2oBZUo/UuaurMnIp5I/AAAAAAAAJUA/LzvbK0fuLsQ/s1600/AD1.JPG" height="150" width="200" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>Alpine Road. The trail is washed <br />out just round the bend</i></span></td></tr></tbody></table><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">A few years ago, a storm washed out a short section of the trail about half a mile up, and the local authority constructed a bypass trail. About a quarter of a mile long, it is steep, narrow, twisted, and a constant staircase of tree roots protruding from the dirt floor. A brutal climb going up and a thrilling (beginners might say terrifying) descent on the way back. Mountain bike heaven.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">There is one particularly tricky section right at the start. This is where you can develop the key abilities you need to be able to prove mathematical theorems.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="font-family: inherit;"><span style="color: #262626;">So you have a choice. Read Polya's </span><a href="http://www.amazon.com/How-Solve-It-Mathematical-Princeton/dp/069111966X/ref=sr_1_1?ie=UTF8&qid=1390827950&sr=8-1&keywords=polya+solve" target="_blank"><span style="color: #0000e9;">classic book</span></a><span style="color: #262626;">, or get a mountain bike and find your own version of the Alpine Road ByPass Trail. (Better still: do both!)</span></span><span style="color: #262626; font-family: inherit; text-align: center;"> </span></div><div align="center" class="MsoNormal" style="mso-layout-grid-align: none; mso-pagination: none; text-align: center; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://2.bp.blogspot.com/-dH-BoQNnKT4/Uuau3nJwqhI/AAAAAAAAJUI/ZZC2XVeYlS8/s1600/AD2.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://2.bp.blogspot.com/-dH-BoQNnKT4/Uuau3nJwqhI/AAAAAAAAJUI/ZZC2XVeYlS8/s1600/AD2.JPG" height="300" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>My mountain bike at the start of the bypass trail</i></span></td></tr></tbody></table></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">When I first encountered Alpine Road Dirt a few years ago, it took me many rides before I managed to get up the first short, steep section of the ByPass Trail.</span></span><span style="color: #262626; font-family: inherit; text-align: center;"> </span></div><div align="center" class="MsoNormal" style="mso-layout-grid-align: none; mso-pagination: none; text-align: center; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;"><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-YIXIk3Sb9Sw/UuavQgUSzwI/AAAAAAAAJUQ/V0t4kKeQyzQ/s1600/AD3.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://1.bp.blogspot.com/-YIXIk3Sb9Sw/UuavQgUSzwI/AAAAAAAAJUQ/V0t4kKeQyzQ/s1600/AD3.JPG" height="300" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>What lies around that sharp left-hand turn?</i></span></td></tr></tbody></table></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">It starts innocently enough</span></span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">because you cannot see what awaits just around that sharp left-hand turn.</span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">After you have made the turn, you are greeted with a short narrow downhill. You will need it to gain as much momentum as you can for what follows.<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; margin-left: 1em; text-align: right;"><tbody><tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-cJYhua1sgP8/UuavfccAWWI/AAAAAAAAJUY/koMPzmk_ph0/s1600/AD4.JPG" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" src="http://1.bp.blogspot.com/-cJYhua1sgP8/UuavfccAWWI/AAAAAAAAJUY/koMPzmk_ph0/s1600/AD4.JPG" height="320" width="240" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>The short, narrow descent</i></span></td></tr></tbody></table><o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">I've seen bikers with extremely strong leg muscles who can plod their way up the wall that comes next, but I can't do it that way. I learned how to get up it by using my problem-solving/theorem-proving skills.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">The first thing was to break the main problem—get up the insanely steep, root strewn, loose-dirt climb</span></span><span style="color: #262626;">—</span><span style="color: #262626;"><span style="font-family: inherit;">into smaller, simpler problems, and solve those one at a time. Classic Polya.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">But it's Polya with a twist</span></span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">and by "twist" I am not referring to the sharp triple-S bend in the climb. The twist in this case is that the penalty for failure is physical, not emotional as in mathematics. I fell off my bike a lot. The climb is insanely steep. So steep that unless you bend really low, with your chin almost touching your handlebar, your front wheel will lift off the ground. That gives rise to an unpleasant feeling of panic that is perhaps not unlike the one that many students encounter when faced with having to prove a theorem for the first time.</span></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://3.bp.blogspot.com/-TxenzDv742A/UuavvZn0HzI/AAAAAAAAJUg/FAOIWGt11jA/s1600/AD5.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://3.bp.blogspot.com/-TxenzDv742A/UuavvZn0HzI/AAAAAAAAJUg/FAOIWGt11jA/s1600/AD5.JPG" height="400" width="300" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>If you are not careful, your front wheel will lift </i></span><br /><span style="font-size: small;"><i>off the ground.</i></span></td></tr></tbody></table><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">The photo above shows the first difficult stretch. Though this first sub-problem is steep, there is a fairly clear line to follow to the right that misses those roots, though at the very least its steepness will slow you down, and on many occasions will result in an ungainly, rapid dismount. And losing momentum is the last thing you want, since the really hard part is further up ahead, near the top in the picture.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Also, do you see that rain- and tire-worn groove that curves round to the right just over half way up</span></span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">just beyond that big root coming in from the left? It is actually deeper and narrower than it looks in the photo, so unless you stay right in the middle of the groove you will be thrown off line, and your ascent will be over. (Click on the photo to enlarge it and you should be able to make out what I mean about the groove. </span><span style="font-family: inherit;"><span style="background-color: white; color: #262626;">Staying in the groove can be tricky at times.</span><span style="color: #262626;">)</span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Still, despite difficulties in the execution, eventually, with repeated practice, I got to the point of being able to negotiate this initial stretch and still have some forward momentum. I could get up on muscle memory. What was once a series of challenging problems, each dependent on the previous ones, was now a single mastered skill.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">[Remember, I don't have super-strong leg muscles. I am primarily a road bike rider. I can ride for six hours at a 16-18 mph pace, covering up to 100 miles or more. But to climb a steep hill I have to get off the saddle and stand on the pedals, using my body weight, not leg power. Unfortunately, if you take your weight off the saddle on a mountain bike on a steep dirt climb, your rear wheel will start to spin and you come to a stop - which on a steep hill means jump off quick or fall. So I have to use a problem solving approach.]<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Once I'd mastered the first sub-problem, I could address the next. This one was much harder. See that area at the top of the photo above where the trail curves right and then left? Here is what it looks like up close.</span></span></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-6HtJJgvPGI4/Uuav8UZY-1I/AAAAAAAAJUo/14e5aDFm7dI/s1600/AD6.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://1.bp.blogspot.com/-6HtJJgvPGI4/Uuav8UZY-1I/AAAAAAAAJUo/14e5aDFm7dI/s1600/AD6.JPG" height="300" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>The crux of the climb/problem. Now it is really steep.</i></span></td></tr></tbody></table><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">(Again, click on the photo to get a good look. This is the mountain bike equivalent of being asked to solve a complex math problem with many variables.)<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Though the tire tracks might suggest following a line to the left, I suspect they are left by riders coming down. Coming out of that narrow, right-curving groove I pointed out earlier, it would take an extremely strong rider to follow the left-hand line. No one I know does it that way. An average rider (which I am) has to follow a zig-zag line that cuts down the slope a bit.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Like most riders I have seen</span></span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">and for a while I did watch my more experienced buddies negotiate this slope to get some clues</span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">I start this part of the climb by aiming my bike between the two roots, over at the right-hand side of the trail. (Bottom right of picture.)</span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">The next question is, do you go left of that little tree root nipple, sticking up all on its own, or do you skirt it to the right? (If you enlarge the photo you will see that you most definitely do not want either wheel to hit it.)<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">The wear-marks in the dirt show that many riders make a sharp left after passing between those two roots at the start, and steer left of the root protrusion. That's very tempting, as the slope is notably less (initially). I tried that at first, but with infrequent success. Most often, my left-bearing momentum carried me into that obstacle course of tree roots over to the left, and though I sometimes managed to recover and swing out to skirt to the left of that really big root, more often than not I was not able to swing back right and avoid running into that tree!<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">The underlying problem with that line was that thin looking root at the base of the tree. Even with the above photo blown up to full size, you can't really tell how tricky an obstacle it presents at that stage in the climb. Here is a closer view.</span></span></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://2.bp.blogspot.com/-WDzHg3gpmmo/UuawG0eq1QI/AAAAAAAAJUw/DnUkB7pSVfI/s1600/AD7.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://2.bp.blogspot.com/-WDzHg3gpmmo/UuawG0eq1QI/AAAAAAAAJUw/DnUkB7pSVfI/s1600/AD7.JPG" height="400" width="300" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>The obstacle course of tree roots that awaits </i></span><br /><span style="font-size: small;"><i>the rider who bears left</i></span></td></tr></tbody></table><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">If you enlarge this photo, you can probably appreciate how that final, thin root can be a problem if you are out of strength and momentum. Though the slope eases considerably at that point, I</span></span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">like many riders I have seen</span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">was on many occasions simply unable to make it either over the root or circumventing it on one side</span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">though all three options would clearly be possible with fresh legs. And on the few occasions I did make it, I felt I just got lucky</span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">I had not mastered it. I had got the right answer, but I had not really solved the problem. So close, so often. But, as in mathematics, close is not good enough.</span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">After realizing I did not have the leg strength to master the left-of-the-nipple path, I switched to taking the right-hand line. Though the slope was considerable steeper (that is very clear from the blown-up photo), the tire-worn dirt showed that many riders chose that option.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Several failed attempts and one or two lucky successes convinced me that the trick was to steer to the right of the nipple and then bear left around it, but keep as close to it as possible without the rear wheel hitting it, and then head for the gap between the tree roots over at the right.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">After that, a fairly clear left-bearing line on very gently sloping terrain takes you round to the right to what appears to be a crest. (It turns out to be an inflection point rather than a maximum, but let's bask for a while in the success we have had so far.)<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Here is our brief basking point.</span></span></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://3.bp.blogspot.com/-9WiIS4gtGe4/UuawQ2ZZHxI/AAAAAAAAJU4/v3i2Q7WE5HI/s1600/AD8.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://3.bp.blogspot.com/-9WiIS4gtGe4/UuawQ2ZZHxI/AAAAAAAAJU4/v3i2Q7WE5HI/s1600/AD8.JPG" height="300" width="400" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>The inflection point. One more detail to resolve.</i></span></td></tr></tbody></table><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">As we oh-so-briefly catch our breath and "coast" round the final, right-hand bend and see the summit ahead, we come</span></span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">very suddenly</span><span style="color: #262626;">—</span><span style="color: #262626; font-family: inherit;">to one final obstacle.</span></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://4.bp.blogspot.com/-08U1zv-QidQ/Uuawbs7j1YI/AAAAAAAAJVA/FqV5sdk50hA/s1600/AD9.JPG" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://4.bp.blogspot.com/-08U1zv-QidQ/Uuawbs7j1YI/AAAAAAAAJVA/FqV5sdk50hA/s1600/AD9.JPG" height="400" width="300" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;"><span style="font-size: small;"><i>The summit of the climb</i></span></td></tr></tbody></table><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">At the root of the problem (sorry!) is the fact that the right-hand turn is actually sharper than the previous photo indicates, almost a switchback. Moreover, the slope kicks up as you enter the turn. So you might not be able to gain sufficient momentum to carry you over one or both of those tree roots on the left that you find your bike heading towards. And in my case, I found I often did not have any muscle strength left to carry me over them by brute force.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">What worked for me is making an even tighter turn that takes me to the right of the roots, with my right shoulder narrowly missing that protruding tree trunk. A fine-tuned approach that replaces one problem (power up and get over those roots) with another one initially more difficult (slow down and make the tight turn even tighter).<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">And there we are. That final little root poking up near the summit is easily skirted. The problem is solved.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">To be sure, the rest of the ByPass Trail still presents several other difficult challenges, a number of which took me several attempts before I achieved mastery. Taken as a whole, the entire ByPass is a hard climb, and many riders walk the entire quarter mile. But nothing is as difficult as that initial stretch. I was able to ride the rest long before I solved the problem of the first 100 feet. Which made it all the sweeter when I finally did really crack that wall.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Now I (usually) breeze up it, wondering why I found it so difficult for so long.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">Usually? In my next post, I'll use this story to talk about strategies for solving difficult mathematical problems. In particular, I'll look at the role of the subconscious in being able to put together a series of mastered steps in order to solve a big problem. For a very curious thing happened after I took the photos to illustrate this post. I walked back down to collect my bike from the ByPass sign where I'd left it, and rode up to continue my ride.<o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="font-family: inherit;"><i><span style="color: #262626;">It took me four attempts to complete that initial climb!</span></i><span style="color: #262626;"><o:p></o:p></span></span></div><div class="MsoNormal" style="margin-bottom: 18.2pt; mso-layout-grid-align: none; mso-pagination: none; text-autospace: none;"><span style="color: #262626;"><span style="font-family: inherit;">And therein lies one of the biggest secrets of being able to solve a difficult math problem.</span></span></div><div class="MsoNormal"><i><span style="color: #262626;"><span style="font-family: inherit;">To be continued ...</span></span></i><o:p></o:p><br /><i><span style="color: #262626;"><span style="font-family: inherit;"><br /></span></span></i><span style="color: #262626;">See "</span><a href="http://devlinsangle.blogspot.com/2014/03/how-mountain-biking-can-provide-key-to.html" target="_blank">How Mountain Biking Can Provide the Key to the Eureka Moment</a>"</div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com2tag:blogger.com,1999:blog-2516188730140164076.post-24418216704169069332014-01-03T07:47:00.000-05:002014-01-03T09:49:36.719-05:0023 and Me. Play it again, SamIt’s one of the most famous lines from one of the most famous movies of all time, <i>Casablanca</i>. Except it’s not what Ilsa, played by Ingrid Bergman, actually said, which was “Play it once, Sam, for old times' sake . . . [NO RESPONSE] . . . Play it, Sam. Play 'As Time Goes By.'”<br /><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">This month’s column is in response to the emails I receive from time to time asking for a reference to articles I have written for the MAA since I began on that mathemaliterary journey back in 1991. (Yes, I just made that word up. Google returns nothing. But it soon will.)</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I first started writing monthly articles for the MAA back in September 1991 when I took over as editor of the Association’s monthly print magazine <i>FOCUS</i>. When I stepped down as <i>FOCUS</i> editor in January 1996, the MAA launched its website, and along with it <i>Devlin’s Angle</i>. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">During that time, in addition to moving from print to online, the MAA website went through two overhauls, leaving the archives spread over three volumes:</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">January 1996 – December 2003</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_archives.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_archives.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">January 2004 – July 2011</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devangle.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devangle.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">August 2011 – present</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Throughout those 23 years, I’ve wandered far and wide across the mathematical and mathematics education landscape. But three ongoing themes emerged. None of them was planned. In each case, I simply wrote something that generated interest – and for one theme considerable controversy – and as a result I kept coming back to it.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I continue to receive emails asking about articles I wrote on the first two of those three themes, and the third is still very active. So I am devoting this month’s column to providing an index to those three themes.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I’ll start with the most controversial: what is multiplication? This began innocently enough, with a throw-away final remark to a piece I wrote back in 2007. I little knew the firestorm I was about to unleash.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><b>What is Multiplication?</b></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">September 2007, What is conceptual understanding?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_09_07.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_09_07.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">June 2008, It Ain't No Repeated Addition</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_06_08.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_06_08.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">July-August 2008, It's Still Not Repeated Addition</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_0708_08.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_0708_08.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">September 2008, Multiplication and Those Pesky British Spellings</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_09_08.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_09_08.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">December 2008, How Do We Learn Math?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_12_08.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_12_08.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">January 2009, Should Children Learn Math by Starting with Counting?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_01_09.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_01_09.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">January 2010, Repeated Addition - One More Spin</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_01_10.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_01_10.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">January 2011, What Exactly is Multiplication?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_01_11.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_01_11.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">November 2011, How multiplication is really defined in Peano arithmetic</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2011_11_01_archive.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2011_11_01_archive.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><b>Mathematical Thinking</b></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I first started making the distinction between mathematics and mathematical thinking in the early 1990s, when an extended foray into mathematical linguistics and then sociolinguistics led to an interest in mathematical cognition that continues to this day.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">April 1996, Are Mathematicians Turning Soft?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlinangle_april.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlinangle_april.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">October 1996, Wanted: A New Mix</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/october.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/october.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">September 1999, What Can Mathematics Do For The Businessperson?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_9_99.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_9_99.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">January 2008, American Mathematics in a Flat World</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_01_08.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_01_08.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">February 2008, Mathematics for the President and Congress</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_02_08.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_02_08.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">October 2009, Soft Mathematics</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_10_09.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_10_09.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">July 2010, Wanted: Innovative Mathematical Thinking</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.maa.org/external_archive/devlin/devlin_07_10.html" target="_blank"><span style="color: #00000a;">http://www.maa.org/external_archive/devlin/devlin_07_10.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">September 2012, What <i>is</i>mathematical thinking?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2012/08/what-is-mathematical-thinking.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2012/08/what-is-mathematical-thinking.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><b>MOOCS</b></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">No introduction necessary. MOOCs are constantly in the news. Though I was one of the early pioneers in developing the Stanford MOOCs that generated all the media interest in 2012, and I believe the first person to offer a mathematics MOOC (Introduction to Mathematical Thinking), the idea goes back to a course given at Athabasca University in Canada, back in 2008.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">May 2012, Math MOOC – Coming this fall. Let’s Teach the World</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2012_05_01_archive.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2012_05_01_archive.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">November 2012, MOOC Lessons</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2012_11_01_archive.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2012_11_01_archive.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">December 2012, The Darwinization of Higher Education</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2012/12/the-darwinization-of-higher-education.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2012/12/the-darwinization-of-higher-education.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">January 2013, R.I.P. Mathematics? Maybe.</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2013_01_01_archive.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2013_01_01_archive.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">February 2013, The Problem with Instructional Videos</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2013_02_01_archive.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2013_02_01_archive.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">March 2013, Can we make constructive use of machine-graded, multiple-choice questions in university mathematics education?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2013_03_01_archive.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2013_03_01_archive.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">September 2013, Two Startups in One Week</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2013_09_01_archive.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2013_09_01_archive.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><b>More about MOOCs</b></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">In addition to the MOOC articles listed above, I have also written articles about the topic in my own blog MOOCtalk.org and for the <i>Huffington Post</i>. Here are the references:</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">MOOCTALK</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">An irregular series of posts starting on May 5, 2012</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://mooctalk.org/" target="_blank"><span style="color: #00000a;">http://mooctalk.org</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><i>HUFFINGTON POST</i></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">December 2013, MOQR, Anyone? Learning by Evaluating</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.com/2013_12_01_archive.html" target="_blank"><span style="color: #00000a;">http://devlinsangle.blogspot.com/2013_12_01_archive.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">March 2, 2013, MOOCs and the Myths of Dropout Rates and Certification</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.huffingtonpost.com/dr-keith-devlin/moocs-and-the-myths-of-dr_b_2785808.html" target="_blank"><span style="color: #00000a;">http://www.huffingtonpost.com/dr-keith-devlin/moocs-and-the-myths-of-dr_b_2785808.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">March 27, 2013, Can Massive Open Online Courses Make Up for an Outdated K-12 Education System?</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.huffingtonpost.com/dr-keith-devlin/massive-open-online-courses_b_2946591.html" target="_blank"><span style="color: #00000a;">http://www.huffingtonpost.com/dr-keith-devlin/massive-open-online-courses_b_2946591.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">August 19, 2013, MOOC Mania Meets the Sober Reality of Education</div><div style="margin-bottom: 0in;"><span style="color: blue;"><span lang="zxx"><u><a href="http://www.huffingtonpost.com/dr-keith-devlin/mooc_b_3741625.html" target="_blank"><span style="color: #00000a;">http://www.huffingtonpost.com/dr-keith-devlin/mooc_b_3741625.html</span></a></u></span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">November 18, 2013, Why MOOCs May Still Be Silicon Valley's Next Grand Challenge</div><u style="color: blue;"><a href="http://www.huffingtonpost.com/dr-keith-devlin/why-moocs-remain-silicon-_b_4289739.html" target="_blank"><span style="color: #00000a;">http://www.huffingtonpost.com/dr-keith-devlin/why-moocs-remain-silicon-_b_4289739.html</span></a></u>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-80828164183648182092013-12-02T16:35:00.000-05:002013-12-02T16:38:51.435-05:00MOQR, Anyone? Learning by EvaluatingMany colleges and universities have a mathematics or quantitative reasoning requirement that ensures that no student graduates without completing at least one sufficiently mathematical course.<br /><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Recognizing that taking a regular first-year mathematics course—designed for students majoring in mathematics, science, or engineering—to satisfy a QR requirement is not educationally optimal (and sometimes a distraction for the instructor and the TAs who have to deal with students who are neither motivated nor well prepared for the full rigors and pace of a mathematics course), many institutions offer special QR courses. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I’ve always enjoyed giving such courses, since they offer the freedom to cover a wide swathe of mathematics—often new or topical parts of mathematics. Admittedly they do so at a much more shallow depth than in other courses, but a depth that was always a challenge for most students who signed up.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Having been one of the pioneers of so-called “transition courses” for incoming mathematics majors back in the 1970s, and having given such courses many times in the intervening years, I never doubted that a lot of the material was well suited to the student in search of meeting a QR requirement. The problem with classifying a transition course as a QR option is that the goal of preparing an incoming student for the rigors of college algebra and real analysis is at odds with the intent of a QR requirement. So I never did that.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Enter MOOCs. A lot of the stuff that is written about these relatively new entrants to the higher education landscape is unsubstantiated hype and breathless (if not fearful) speculation. The plain fact is that right now no one really knows what MOOCs will end up looking like, what part or parts of the population they will eventually serve, or exactly how and where they will fit in with the rest of higher education. Like most others I know who are experimenting with this new medium, I am treating it very much as just that: an experiment. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">The first version of my MOOC <span style="color: blue;"><span lang="zxx"><u><a href="https://www.coursera.org/course/maththink" target="_blank">Introduction to Mathematical Thinking</a></u></span></span>, offered in the fall of 2012, was essentially the first three-quarters of my regular transition course, modified to make initial entry much easier, delivered as a MOOC. Since then, as I have experimented with different aspects of online education, I have been slowly modifying it to function as a QR-course, since improved quantitative reasoning is surely a natural (and laudable) goal for online courses with global reach—that “free education for the world” goal is still the main MOOC-motivator for me. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I am certainly not viewing my MOOC as an online course to satisfy a college QR requirement. That may happen, but, as I noted above, no one has any real idea what role(s) MOOCs will end up fulfilling. Remember, <i>in just twelve months</i>, the Stanford MOOC startup Udacity, which initiated all the media hype, <span style="color: blue;"><span lang="zxx"><u><a href="http://www.fastcompany.com/3021473/udacity-sebastian-thrun-uphill-climb" target="_blank">went from</a></u></span></span> “teach the entire world for free” to “offer corporate training for a fee.” (For my (upbeat) commentary on this rapid progression, see <span style="color: blue;"><span lang="zxx"><u><a href="http://www.huffingtonpost.com/dr-keith-devlin/why-moocs-remain-silicon-_b_4289739.html" target="_blank">my article in the <i>Huffington Post</i></a></u></span></span>.)</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Rather, I am taking advantage of the fact that free, no-credential MOOCs currently provide a superb vehicle to experiment with ideas both for classroom teaching and for online education. Those of us at the teaching end not only learn what the medium can offer, we also discover ways to improve our classroom teaching; while those who register as students get a totally free learning opportunity. (Roughly three-quarters of them already have a college degree, but MOOC enrollees also include thousands of first-time higher education students from parts of the world that offer limited or no higher education opportunities.)</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">The biggest challenge facing anyone who wants to offer a MOOC in higher mathematics is how to handle the fact that many of the students will never receive expert feedback on their work. This is particularly acute when it comes to learning how to prove things. That’s already a difficult challenge in a regular class, as made clear in <span style="color: blue;"><span lang="zxx"><u><a href="http://mathbabe.org/2012/04/12/how-to-teach-someone-how-to-prove-something/" target="_blank">this great blog post</a></u></span></span> by “mathbabe” Cathy O’Neil. In a MOOC, my current view is it would be unethical to try. The last thing the world needs are (more) people who <i>think</i> they know what a proof is, but have never put that knowledge to the test.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">But when you think about it, the idea behind QR is not that people become mathematicians who can prove things, rather that they have a base level of quantitative literacy that is necessary to live a fulfilled, rewarding life and be a productive member of society. Being able to prove something mathematically is a <i>specialist</i> skill. The important general ability in today’s world is to have a good understanding of the nature of the various kinds of arguments, the special nature of mathematical argument and its role among them, and an ability to judge the soundness and limitations of any particular argument.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">In the case of mathematical argument, acquiring that “<i>consumer’s</i> understanding” surely involves having some experience in trying to construct very simple mathematical arguments, but far more what is required is being able to <i>evaluate</i> mathematical arguments. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">And that can be handled in a MOOC. Just present students with various mathematical arguments, some correct, others not, and machine-check if, and how well, they can determine their validity.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Well, that leading modifier “just” in that last sentence was perhaps too cavalier. There clearly is more to it than that. As always, the devil is in the details. But once you make the shift from viewing the course (or the proofs part of the course) as being about <i>constructing</i> proofs to being about <i>understanding</i> and <i>evaluating</i> proofs, then what previously seemed hopeless suddenly becomes rife with possibilities.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I started to make this shift with the last session of my MOOC this fall, and though there were significant teething troubles, I saw enough to be encouraged to try it again—with modifications—to an even greater extent next year.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Of course, many QR courses focus on appreciation of mathematics, spiced up with enough “doing math” content to make the course defensibly eligible for QR fulfillment. What I think is far less common—and certainly new to me—is using the <i>evaluation of proofs</i> as a major learning vehicle.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">What makes this possible is that the Coursera platform on which my MOOC runs has developed a peer review module to support peer grading of student papers and exams. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">The first times I offered my MOOC, I used peer evaluation to grade a Final Exam. Though the process worked tolerably well for grading student mathematics exams—a lot better than I initially feared—to my eyes it still fell well short of providing the meaningful grade and expert feedback a professional mathematician would give. On the other hand, the benefit to the students that came from seeing, and trying to evaluate, the proof attempts of other students, and to provide feedback, was significant—both in terms of their gaining much deeper insight into the concepts and issues involved, and in bolstering their confidence.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">When the course runs again in a few week's time, the Final Exam will be gone, replaced by a new course culmination activity I am calling Test Flight.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">How will it go? I have no idea. That’s what makes it so interesting. Based on my previous experiments, I think the main challenges will be largely those of implementation. In particular, years of educational high-stakes testing robs many students of the one ingredient essential to real learning: being willing to take risks and to fail. As young children we have it. Schools typically drive it out of us. Those of us lucky enough to end up at graduate school reacquire it—we have to.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I believe MOOCs, which offer community interaction through the semi-anonymity of the Internet, offer real potential to provide others with a similar opportunity to re-learn the power of failure. Test Flight will show if this belief is sufficiently grounded, or a hopelessly idealistic dream! (Test flights do sometimes crash and burn.)</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">The more people learn to view failure as an essential constituent of good learning, the better life will become for all. As a world society, we need to relearn that innate childhood willingness to try and to fail. A society that does not celebrate the many individual and local failures that are an inevitable consequence of trying something new, is one destined to fail globally in the long term.</div><div style="margin-bottom: 0in;"><br /></div><br /><div style="margin-bottom: 0in;">For those interested, I’ll be describing Test Flight, and reporting on my progress (including the inevitable failures), in my blog <span style="color: blue;"><span lang="zxx"><u><a href="http://mooctalk.org/" target="_blank">MOOCtalk.org</a></u></span></span>as the experiment continues. (The next session starts on February 3.)</div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-23052003462772141312013-11-04T08:09:00.000-05:002013-11-04T09:30:20.948-05:00The Educational Power of Elementary Arithmetic<div class="MsoNormal"><span style="font-family: inherit;">The trouble with writing about, or quoting, Liping Ma, is that everyone interprets her words through their own frame, influenced by their own experiences and beliefs. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">“Well, yes, but isn’t that true for anyone reading anything?” you may ask. True enough. But in Ma’s case, readers often arrive at diametrically opposed readings. Both sides in the US Math Wars quote from her in support of their positions.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">That happened with the book that brought her to most people’s attention, <a href="http://www.amazon.com/Knowing-Teaching-Elementary-Mathematics-Understanding/dp/0805829091/ref=la_B001I0OP0C_1_1?s=books&ie=UTF8&qid=1383531332&sr=1-1"><i>Knowing and Teaching Elementary Mathematics: Teachers' Understanding of Fundamental Mathematics in China and the United States</i></a>, first published in 1999. And I fear the same will occur with her recent article "<a href="http://www.ams.org/notices/201310/fea-ma.pdf">A Critique of the Structure of U.S. Elementary School Mathematics</a>," published in the November issue of the American Mathematical Society <i>Notices</i>.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Still, if I stopped and worried about readers completely misreading or misinterpreting things I write, <i>Devlin’s Angle</i> would likely appear maybe once or twice a year at most. So you can be sure I am about to press ahead and refer to her recent article regardless. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">My reason for doing so is that I am largely in agreement with what I believe she is saying. Her thesis (i.e., what I understand her thesis to be) is what lay behind the design of <a href="https://www.coursera.org/course/maththink">my MOOC</a> and my recently released <a href="http://innertubegames.net/">video game</a>. (More on both later.)<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Broadly speaking, I think most of the furor about K-12 mathematics curricula that seems to bedevil every western country except <a href="http://www.thedailyriff.com/articles/the-finland-phenomenon-inside-the-worlds-most-surprising-school-system-588.php">Finland</a> is totally misplaced. It is misplaced for the simple, radical (except in <a href="http://www.thedailyriff.com/articles/the-finland-phenomenon-inside-the-worlds-most-surprising-school-system-588.php">Finland</a>) reason that <i>curriculum doesn’t really matter</i>. What matter are teachers. (That last sentence is, by the way, the much sought after “<a href="http://blip.tv/hdnet-news-and-documentaries/dan-rather-reports-finnish-first-6518828">Finnish secret</a>” to good education.) To put it simply:<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">BAD CURRICULUM + GOOD OR WELL-TRAINED TEACHERS = GOOD EDUCATION<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">GOOD CURRICULUM + POOR OR POORLY-TRAINED TEACHERS = POOR EDUCATION<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;">I am very familiar with the Finnish education system. The Stanford </span><a href="http://hstar.stanford.edu/">H-STAR institute</a><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"> I co-founded and direct has been collaborating with Finnish education researchers for over a decade, we host education scholars from Finland regularly, I travel to Finland several times a year to work with colleagues there, I am on the </span><a href="http://www.cicero.fi/international-advisory-board.html">Advisory Board</a><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"> of </span><a href="http://www.cicero.fi/">CICERO Learning</a><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;">, one of their leading educational research organizations, I’ve spoken with members of the Finnish government whose focus is education, and I’ve sat in on classes in Finnish schools. So I know from firsthand experience in the western country that has got it right that teachers are everything and curriculum is at most (if you let it be) a distracting side-issue.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">The only people for whom curriculum really matters are politicians and the politically motivated (who can make political capital out of curriculum) and publishers (who make a lot of financial capital out of it).<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;">But I digress: Finland merely serves to provide an existence proof that providing good mathematics education in a free, open, western society is possible and has nothing to do with curriculum. Let’s get back to Liping Ma’s recent <i>Notices</i> article. For she provides a recipe for how to do it right in the curriculum-obsessed, </span><a href="http://www.washingtonpost.com/blogs/answer-sheet/wp/2013/11/03/gov-chris-christie-yells-at-a-teacher-again/">teacher-denigrating</a><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"> US.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">Behind Ma’s suggestion, as well as behind my MOOC and my video game (both of which I have invested a lot of effort and resources into) is the simple (but so often overlooked) observation that, at its heart, mathematics is not a body of facts or procedures but <i>a way of thinking</i>. Once a person has learned to think that way, it becomes possible to learn and use pretty well any mathematics you need or want to know about, when you need or want it.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">In principle, many areas of mathematics can be used to master that way of thinking, but some areas are better suited to the task, since their learning curve is much more forgiving to the human brain.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">For my MOOC, which is aimed at beginning mathematics students at college or university, or high school students about to become such, I take formalizing the use of language and the basic rules of logical reasoning (in everyday life) as the <i>subject matter</i>, but the <i>focus</i> is as described in the last two words of the course’s title: <i>Introduction to Mathematical Thinking</i>. <o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">Apart from the final two weeks of the course, where we look at elementary number theory and beginning real analysis, there is really no mathematics in my course in the usual sense of the word. We use everyday reasoning and communication as the vehicle to develop mathematical thinking.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">[SAMPLE PROBLEM: Take the famous (alleged) Abraham Lincoln quote, “You can fool all of the people some of the time and some of the people all of the time, but you cannot fool all the people all the time.” What is the simplest and clearest positive expression you can find that states the negation of that statement? Of course, you first have to decide what “clearest”, “simplest”, and “positive” mean.]<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">Ma’s focus in her article is beginning school mathematics. She contrasts the approach used in China until 2001 with that of the USA. The former concentrated on “school arithmetic” whereas, since the 1960s, the US has adopted various instantiations of a “strands” approach. (As Ma points out, since 2001, China has been moving towards a strands approach. By my read of her words, she thinks that is not a wise move.)<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">As instantiated in the NCTM’s 2001 <i>Standards</i> document, elementary school mathematics should cover ten separate strands: number and operations, problem solving, algebra, reasoning and proof, geometry, communication, measurement, connections, data analysis and probability, and representation. <o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">In principle, I find it hard to argue against any of these—<i>provided they are viewed as different facets of a single whole.</i> <o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">The trouble is, as soon as you provide a list, it is almost inevitable that the first system administrator whose desk it lands on will turn it into a tick-the-boxes spreadsheet, and in turn the textbook publishers will then produce massive (hence expensive) textbooks with (at least) ten chapters, one for each column of the spreadsheet. The result is the justifiably maligned “Mile wide, inch deep” US elementary school curriculum.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">It’s not that the idea is wrong in principle. The problem lies in the implementation. It’s a long path from a highly knowledgeable group of educators drawing up a curriculum to what finds its way into the classroom</span></span><span style="color: #141413;">—</span><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">often to be implemented by teachers woefully unprepared (through no fault of their own) for the task, answerable to administrators who serve political leaders, and forced to use textbooks that reinforce the separation into strands rather than present them as variations on a single whole. <o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">Ma’s suggestion is to go back to using arithmetic as the primary focus, as was the case in Western Europe and the United States in the years of yore and China until the turn of the Millennium, and use that to develop all of the mathematical thinking skills the child will require, both for later study and for life in the twenty-first century. I think she has a point. A good point.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">She is certainly not talking about drill-based mastery of the classical Hindu-Arabic algorithms for adding, subtracting, multiplying, and dividing, nor is she suggesting that the goal should be for small human beings to spend hours forcing their analogically powerful, pattern-recognizing brains to become poor imitations of a ten-dollar calculator. What was important about arithmetic in past eras is not necessarily relevant today. Arithmetic can be used to trade chickens or build spacecraft.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">No, if you read what she says, <i>and you absolutely should</i>, she is talking about the rich, powerful structure of the two basic number systems, the whole numbers and the rational numbers.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">Will that study of elementary arithmetic involve lots of practice for the students? Of course it will. A child’s life is full of practice. We are adaptive creatures, not cognitive sponges. But the goal</span></span><span style="color: #141413;">—</span><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">the motivation for and purpose of that practice</span></span><span style="color: #141413;">—</span><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">is developing <i>arithmetic thinking</i>, and moreover doing so in a manner that provides the foundation for, and the beginning of, the more general <i>mathematical thinking</i> so important in today’s world, and hence so empowering for today’s citizens.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">The whole numbers and the rational numbers are perfectly adequate for achieving that goal. You will find pretty well every core feature of mathematics in those two systems. Moreover, they provide an entry point that everyone is familiar with, teacher, administrator, and beginning elementary school student alike. <o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">In particular, a well trained teacher can build the necessary thinking skills and the mathematical sophistication </span></span><span style="color: #141413;">—</span><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">and cover whatever strands are in current favor</span></span><span style="color: #141413;">—</span><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">without having to bring in any other mathematical structure.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">When you adopt the strands approach (pick your favorite flavor), it’s very easy to skip over school arithmetic as a low-level skill set to be “covered” as quickly as possible in order to <i>move on</i> to the “real stuff” of mathematics. But Ma is absolutely right in arguing that this is to overlook the rich potential still offered today by what are arguably (I would so argue) the most important mathematical structures ever developed: the whole and the rational numbers and their associated elementary arithmetics.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"><span style="font-family: inherit;">For what is often not realized is that there is absolutely nothing elementary about elementary arithmetic.<o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;">Incidentally, for my video game, </span><a href="https://vimeo.com/73080023">Wuzzit Trouble</a><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;">, I took whole number arithmetic and built a game around it. If you play it through, finding optimal solutions to all 75 puzzles, you will find that you have to make use of increasingly sophisticated arithmetical reasoning. (Integer partitions, Diophantine equations, algorithmic thinking, and optimization.) <o:p></o:p></span></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;"><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;">I doubt Ma had video game instantiations of her proposal in mind, but when I first read her article, almost exactly when my game was released in the App Store (the </span><a href="https://play.google.com/store/apps/details?id=com.innertubegames.wuzzittrouble&hl=en">Android version</a><span style="color: #141413; mso-bidi-font-family: "Lucida Bright"; mso-bidi-font-size: 41.5pt;"> came a few weeks later) that’s exactly what I saw.</span></span></div><span style="background-color: white; color: #222222; font-family: inherit;"><br /></span><span style="background-color: white; color: #222222; font-family: inherit;">Other games my colleagues and I have designed but not yet built are based on different parts of mathematics. We started with one built around elementary arithmetic because arithmetic provides all the richness you need to develop mathematical thinking, and we wanted our first game to demonstrate the potential of game-based learning in thinking-focused mathematical education (as opposed to the more common basic-skills focus of most mathematics-educational games). In starting with an arithmetic-based game, we were (at the time unknowingly) endorsing the very point Ma was to make in her article.</span>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com4tag:blogger.com,1999:blog-2516188730140164076.post-39240800490476318532013-10-01T15:22:00.000-04:002013-10-05T13:09:57.879-04:00Math Ed? Sometimes It Takes a Team<div class="MsoNormal"><span style="font-family: inherit;">In </span><a href="http://devlinsangle.blogspot.com/2013/09/two-startups-in-one-week.html" style="font-family: inherit;">last month’s column</a><span style="font-family: inherit;">, I reflected on how modern technology enables one person—in my case an academic</span>—<span style="font-family: inherit;">to launch enterprises with (potential) global reach without (i) money and (ii) giving up his day job. That is true, but technology does not replace expertise and its feeder, experience.</span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">In the case of <a href="https://www.coursera.org/course/maththink">my MOOC</a>, now well into its third offering, I’ve been teaching transition courses on mathematical thinking since the late 1970s, and am able to draw on a lot of experience as to the difficulties most students have with what for most of them is a completely new side to mathematics. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Right now, as we get into elementary, discrete number theory, the class (the 9,000 of 53,000 registrants still active) is struggling to distinguish between division</span>—<span style="font-family: inherit;">a binary operation on rationals that yields a rational number for a given pair of integers or rationals</span>—<span style="font-family: inherit;">and divisibility</span>—<span style="font-family: inherit;">a relation between pairs of integers that is either true or false for any given pair of integers. Unused to distinguishing between different number systems, they suddenly find themselves lost with what they felt they knew well, namely elementary arithmetic. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Anyone who has taught a transition course will be familiar with this problematic rite of passage. I suspect I am not alone in having vivid memories of when I myself went through it, even though it was many decades ago!<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">As a result of all those years teaching this kind of material, I pretty well know what to expect in terms of student difficulties and responses, so can focus my attention on figuring out how to make it work in a MOOC. I know how to filter and interpret the comments on the discussion forum, having watched up close many generations of students go through it. As a result, doing it in a MOOC format with a class spread across the globe is a fascinating experiment, when it could so easily have been a disaster. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">My one fear is that, because the course pedagogy is based on <a href="http://www.youtube.com/watch?v=f6t6WiWYdgY">Inquiry-Based Learning</a>, it may be more successful with experienced professionals (of whom I have many in the class), rather than the course’s original target audience of recent high school graduates. In particular, I suspect it is the latter who constantly request that I show them how to solve a problem before expecting them to do so. If all students have been exposed to is instructional teaching, and they have never experienced having to solve a novel problem</span>—<span style="font-family: inherit;">to figure it out for themselves</span>—<span style="font-family: inherit;">it is probably unrealistic to expect them to make that leap in a Web-based course. But maybe it can be made to work. Time will tell.</span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">The other startup I wrote about was my video game company. That is a very different experience, since almost everything about this is new to me. Sure, I’ve been studying and writing about video game learning for many years, and have been playing video games for the same length of time. But designing and producing a video game, and founding a company to do it, are all new. Although we describe <a href="http://innertubegames.net/">InnerTube Games</a> as “Dr. Keith Devlin’s video game company,” and most of the <a href="http://innertubegames.net/news.html">reviews</a> of our first release referred to <i>Wuzzit Trouble</i> as “Keith Devlin’s mathematics video game,” that was like referring to The Rolling Stones as “Mick Jagger’s rock group.” Sure he was out in front, but it was the entire band that gave us all those great performances.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">In reality, I brought just three new things to our video game design. The first is our strong focus on mathematical thinking (the topic of my MOOC) rather than the mastery of symbolic skills (which is what 99% of current math ed video games provide). The second is that the game should embed at least one piece of deep, conceptual mathematics. (Not because I wanted the players to learn that particular piece of mathematics. Rather that its presence would ensure a genuine <i>mathematical</i>experience.) The third is the design principle that the video game should be thought of as an <a href="https://vimeo.com/73327014">instrument on which you “play math,”</a> analogous to the piano, an instrument on which you play music.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">In fact, I was not alone among the <a href="http://innertubegames.net/team.html">company co-founders</a> in favoring the mathematical thinking approach. One of us, Pamela, is a former middle-school mathematics teacher and an award winning producer of educational television shows, and she too was not interested in producing the 500<sup>th</sup>animated-flash-card, skills-mastery app. (Nothing wrong with that approach, by the way. It’s just that the skills-mastery sector is already well served, and we wanted to go instead for something that is woefully under-served.) I may know a fair amount about mathematics and education, and I use technology, but that does not mean I'm an expert in the use of various media in education. But Pamela is.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">And this is what this month’s column is really about: the need for an experienced and talented team to undertake anything as challenging as designing and creating a good educational learning app. Though I use my own case as an example, the message I want to get across is that if, like me, you think it is worthwhile adding learning apps and video games to the arsenal of media that can be used to provide good mathematics learning, then you need to realize that one smart person with a good idea is not going to be anything like enough. We need to work in teams with people who bring different expertise.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">I’ve written extensively in my blog <a href="http://profkeithdevlin.org/">profkeithdevlin.org</a> about the problems that must be overcome to build good learning apps. In fact, because of the history behind my company, we set our bar even higher. We decided to create video games that had all the features of good commercial games developed for entertainment. Games like <i>Angry Birds</i>or <i>Cut the Rope</i>, to name two of my favorites. Okay, we knew that, with a mathematics-based game, we are unlikely to achieve the dizzying download figures of those industry-leading titles. But they provided excellent exemplars in game structure, game mechanics, graphics, sounds, game characters, etc. In the end, it all comes down to engagement, whether the goal is entertainment and making money or providing good learning.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">In other words, we saw (and see) ourselves not as an “educational video game company” but as a “video game company.” But one that creates video games built around important mathematical concepts. (In the case of <i>Wuzzit Trouble</i>, those concepts are integer arithmetic, integer partitions, and Diophantine equations.)<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Going after that goal requires many different talents. I’ve already mentioned Pamela, our Chief Learning Officer. I met her, together with my other two co-founders, when I worked with them for several years on an educational video game project at a large commercial studio. That project never led to a released product, but it provided all four of us with the opportunity to learn a great deal about the various crucial components of good video game design that embeds good learning. Enough to realize, first, that we all needed one another, and second that we could work well together. (Don’t underestimate that last condition.)<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">By working alongside video game legend John Romero, I learned a lot about what it takes to create a game that players will want to play. Not enough to do so myself. But enough to be able to work with a good game developer to inject good mathematics into such a game. That’s Anthony, the guy on our team who takes a mathematical concept and turns it into a compelling game activity. (The guy who can give me three good reasons why my “really cool idea” really won’t work in a game!) Pamela, Anthony, and I work closely together to produce fun game activities that embed solid mathematical learning, each bringing different perspectives. Take any one of us out of the picture, and the resulting game would not come close to getting those great release reviews we did.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">And without Randy, there would not even be a game to get reviewed! Video games are, after all, a business. (At some point, we will have to bring in revenue to continue!) The only way to create and distribute quality games is to create a company. And yes, that company has to create and market a product</span>—<span style="font-family: inherit;">something that’s notoriously difficult. (Google “why video game companies fail.”) Randy (also a former teacher) was the overall production manager of the project we all worked on together, having already spent many years in the educational technology world. He’s the one who keeps everything moving.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Like it or not, the world around us is changing rapidly, and with so many things pulling on our students’ time, it’s no longer adequate to sit back on our institutional reputations and expect students to come to us and switch off the other things in their lives while they take our courses. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">One case: I cannot see MOOCs replacing physical classes with real professors, but they sure are already changing the balance. And you don’t have to spend long in a MOOC to see the similarities with MMOs (massively multiplayer online games).<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">We math professoriate long ago recognized we needed to acquire the skills to prepare documents using word processing packages and LaTeX, and to prepare Keynote or PowerPoint slides. Now we are having to learn the rudiments of learning management systems (LMSs), video editing, the creation of applets, and the use of online learning platforms. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Creating video games is perhaps more unusual, since it requires so many different kinds of expertise, and I am only doing that because a particular professional history brought me into contact with the gaming industry. But plenty of mathematical types have created engaging math learning apps, and some of them are really very good.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Technology not only makes all of these developments possible, it makes it imperative that, as a community, we get involved. But in the end, it’s people, not the technology, that make it happen. And to be successful, those people may have to work in collaborative teams. </span><o:p></o:p></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-55763125322919288222013-09-04T08:19:00.001-04:002013-09-04T08:34:00.776-04:00Two Startups in One Week<div class="MsoNormal"><span style="font-family: inherit;">Last week turned out to be far more hectic than most, with the simultaneous launch of two startups I have been involved in for the past few years.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">When I went into the life of academic mathematics some 42 years ago, I could never have imagined ever writing such a sentence. Nor, for that matter, would I have had the faintest idea what a “startup” was. It’s a measure of how much society has changed since 1971, when I transitioned from being a “graduate student” to a “postdoc,” that today everyone knows what a startup is, and many of my doctorate-bearing academic colleagues have, as a sideline to their academic work, started up labs, centers, or companies. What was once exceptional is now commonplace.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Massive changes in technology have made it, while not exactly easy, at least <i>possible</i> for anyone in academia to become an “edupreneur,” to use (just once, I promise) one of the more egregious recent manufactured words. This means that, when our academic work leads to a good idea or a product we think could be useful to many of our fellow humans, we don’t have to sit back and hope that one day someone will come along and turn it into something people can access or use. We can make it available to them ourselves.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">MOOCs are one of the most recent examples. If any of us in the teaching business finds we have developed a course that students seemed to have benefited from and we are proud of, we can (at least to some extent) bottle it and make it available to a much wider audience. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Of course, we have had versions of that ability since the invention of the printing press. Today, millions of people, academics and non-academics alike, use those printing press descendants, websites and blogs, to achieve a much wider audience for their written word.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">A somewhat smaller (but growing) number have used platforms such as YouTube and Vimeo to make video-recordings of their lectures widely available. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">To some extent, MOOCs can be viewed as an extension of both of those Internet media developments. A MOOC sets out to achieve the very ambitious goal of bottling <i>an entire college course</i> and making it available to the entire world—or at least, that part of the world with broadband access.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">The launch this past weekend of the third iteration of my constantly-evolving MOOC on <a href="https://www.coursera.org/course/maththink">Mathematical Thinking</a> was one of the two startups that gobbled up massive amounts of my time over the past few weeks. Even though, having given essentially the same course twice before, the bulk of the preparatory work was done, implementing the changes I wanted to make and re-setting all the item release dates/times and the various student submission deadlines was still a huge undertaking. For with a MOOC, pretty well everything for the entire course needs to be safely deposited on (in my case, with my MOOC on Coursera) Amazon’s servers before the first of my 41,000 registered students logged on over the weekend.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">When you think about it, the very fact that a single academic can do something like this, is pretty remarkable. What makes it possible is that all the components are readily available. To go into the MOOC business, all you need is a laptop, a word processor (and LaTeX, if you are giving a math course), possibly a slide package such as PowerPoint, some kind of video recording device (I use a standard, $900 consumer camcorder, others use a digital writing tablet), a small microphone (possibly the one already built in to your laptop), and a cheap consumer video editing package (I use Premiere Elements, which comes in at around $90). Assuming you already have the laptop and a standard office software package, you can set up in the MOOC business for about $1500.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Sure, it helps if your college or university gives you access to the open source MOOC platform edX, or is willing to enter an agreement with, say, the MOOC platform provider Coursera. But if not, there are options such as YouTube, websites, Wikis, and blogs, all freely available.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">My second startup was supposed to launch at least a month before my MOOC, but a major hacking event at Apple’s Developer Site delayed their release of the first (free) mathematical thinking mobile game designed by my small educational software company, <a href="http://innertubegames.net/">InnerTube Games</a>. Both launches falling in the same week is not something I’d want to do again!<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Why form a company to create and distribute mathematics education video games that incorporate some of the findings and insights I’d developed over several years of research? The brutal answer is, I had no other viable option. Though several years of research had convinced me that it was possible to design and build “instruments” on which you can “play” parts of mathematics, in the same way a musical instrument such as a piano can be used to play music (in both cases by passing the need for static symbolic representations on a page, which are known to be a huge barrier to learning for many people), I simply was not successful in convincing funders it was a viable approach.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Clearly then, I had to build at least one such instrument. More precisely, I had to team up with a small number of friends who brought the necessary expertise I did not have. Again, a few years ago, it would have been impossible for an academic to found and build a small company and create and launch a product in my spare time. But today, anyone can.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Sure, even more so than with MOOCs, to form and operate an educational software company, you need to work with other people</span>—<span style="font-family: inherit;">three in my case. (That, at least, has been my experience.) But the key point is, the technology and the resources infrastructure make it possible. You don’t have to give up your day job as an academic to do it! And just as a MOOC provider (or a YouTube, website, blogging platform combo) takes care of the distribution of your course, so too the Web (in my case, in the form of Apple’s App Store) can make your creation available to the world. At no cost.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">We are not talking about enterprises designed with the purpose of making money here</span>—<span style="font-family: inherit;">I am essentially in the same game as the writing of academic works or textbooks, and in my case less so, since my books cost money but my MOOC and my game are free. Rather we are making use of a global infrastructure to make our work widely accessible. If that infrastructure involves for-profit MOOC platforms or software companies, so be it.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">The fact is, it has never been as easy as it is today for each one of us to take an idea or something we have created and make it available to a wide audience. Sure, for both my examples, I have left a lot unsaid, focusing on one particular aspect. (Take a glance at my video game website to see who else was involved in that particular enterprise and the experience they brought to the project. That was a team effort if ever there was!) But the key fact is, it is now possible!<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">For more about my MOOC, and MOOCs in general, see my blog <a href="http://mooctalk.org/">MOOCtalk.org</a>. For my findings and thoughts on mathematics education, see many of the posts on my other blog <a href="http://profkeithdevlin.org/">profkeithdevlin.org</a> together with some of the articles and videos linked to on the <a href="http://innertubegames.net/">InnerTube Games</a> website.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">And for another (dramatic) example of how one person with a good idea can quickly reach a global audience, see Derek Muller’s superb STEM education resource <a href="http://www.youtube.com/user/1veritasium">Veritasium</a>. </span><o:p></o:p></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-55655387910022815472013-08-01T14:55:00.000-04:002013-08-01T18:27:48.328-04:00 “Will this (mathematics) be of any use?”<i>Readers who follow me on </i><span style="color: blue;"><span lang="zxx"><u><a href="https://twitter.com/profkeithdevlin"><i>Twitter</i></a></u></span></span><i>will have noticed many tweets on the recent revelations about illegal NSA surveillance. Here is why I think that none of us in mathematics and mathematics education can ignore that debate.</i><br /><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">There’s a popular conception that mathematicians are unworldly, and that mathematics is, at its heart, walled off from the real world, its pursuit a form of escapism that takes the pursuer into a realm of pure, abstract thoughts.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Certainly, that’s a general sense of mathematics that I held for many years. Yes, like all my fellow mathematicians, I always knew that mathematics – all of it – arose, directly or indirectly, from real world problems, and that any branch of mathematics having any discipline-internal significance almost always turns out to have real-world applications. But neither of those was why I did mathematics. For most of my life as a mathematician, I simply did not care about the history or application of what I was doing. It was all about the chase – the search for new knowledge in a beautiful domain.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Early on in my career, when more politically active colleagues urged me to boycott conferences and workshops funded by NATO (a big issue back in the 1970s), or to avoid applying for research funds from commercial or military sources, I essentially turned a deaf ear to what they were saying, and got on with the work that interested me. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">As a mathematician working in axiomatic set theory, with particular foci on the properties of sets of large infinite cardinality and on undecidability proofs, I felt fairly confident that nothing I did would ever find practical application, so for me the issue was purely one of where the money came from to support my research. I felt “clean,” and not under any moral pressure regarding potential unethical uses being made of my work.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">True, I was aware that the famous early twentieth century mathematician G. H. Hardy had made the same claim about his work in number theory, yet in the mid-1970s his work found highly significant application in the design of secure cryptographic systems. But I felt that a similar outcome was unlikely in the case of infinitary set theory. (I am no longer quite as sure about that; I speculated about possible applications of Cantor’s set theory in my <span style="color: blue;"><span lang="zxx"><u><a href="http://devlinsangle.blogspot.co.uk/2013_06_01_archive.html">June column</a></u></span></span>.)</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">I think we all have to address the morality-of-possible-applications question about our work as mathematicians at one time or another. Some, from Archimedes to Alan Turing, have actively engaged in military research; others try to avoid any direct contact with commercial or warfare-related activities.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">The rise of math-based corporations such as Google that form a large and influential part of today’s global world, and the closely related growth of the modern, math-driven security state, as iconicized by the NSA, make it impossible to maintain any longer the fiction (for such it always was) that we can pursue mathematics as a pure activity, separate from applications, be they good or ill.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">The uncomfortable fact is, we are in no different a situation than manufacturers of sporting guns who deny any agency when their product is used to kill people. (Yes, people pull the trigger, but as comedian Eddie Izzard <span style="color: blue;"><span lang="zxx"><u><a href="http://www.youtube.com/watch?v=KsN0FCXw914">pointed out</a></u></span></span>, “the gun helps.”) </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">If we want to be able to maintain that our work will not play a role in someone’s death, torture, or incarceration – or in someone else achieving enormous wealth and power – our only option is to not go into mathematics in the first place. The subject is simply way too powerful as a force – for good or for evil.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Shortly after September 11, 2001, I was asked to join a research project funded by the U.S. intelligence service. For me, that was my crunch time. The work that led to that invitation was an outgrowth (described in my 1995 book <span style="color: blue;"><span lang="zxx"><u><a href="http://www.amazon.com/Logic-Information-Keith-Devlin/dp/0521499712/ref=sr_1_1?ie=UTF8&qid=1375338919&sr=8-1&keywords=devlin+logic+and+information"><i>Logic and Information</i></a></u></span></span>) of my earlier research in mathematical logic and set theory. Like it or not, I was already in deep. To say no to that invitation would have been every bit a positive action as to say yes. Sitting on the fence was not a possibility. I was a mathematician. I’d already made the gun.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">As the Google founders Larry Page and Sergei Brin eventually discovered, “Do no evil” is a wonderful grounding principle, but the power of mathematics renders it an impossible goal to achieve. The best we can do is try to make our voice heard, as many mathematicians and nuclear physicists did during the Cold War, who spoke publicly about the massive scale of the danger raised by nuclear weapons.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Finding out (as I have over the past few weeks) that the work I’d done over the past twelve years – for various branches of the U.S. government (intelligence and military) and for commercial enterprises (in my case, the video game industry) – was part of a body of research that had been subverted (as I see it) to create a massive global surveillance framework, I felt I could not remain silent. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Not because I felt that I, as an individual, did anything of significance. I worked on non-classified projects, and made no major breakthroughs. I was a very tiny cog in a very big machine. (If “they” are keeping an eye on me, they are definitely wasting our tax dollars!) </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">But I did take the money and I did do the work. I don’t regret doing so. The fact is, I’d made the crucial choice long before 2001; back in my youth when I decided to become a mathematician. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Those of us in mathematics education have always told our students that math is useful. In today’s world more than ever, we cannot at the same time pretend it is free of moral issues. Agnosticism is not an option (if it ever really was). To say or do <i>nothing</i> is inescapably a positive act, just as significant as saying or doing <i>something</i>. </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">We humans have created our mathematics, and used it to help shape our world. Now we have to live in it. Not only are we the ones who bear a large responsibility for that world, we are also, by our very expertise, the ones who (in many fundamental ways) understand it best. (It often seems that only the mathematically sophisticated really appreciate that an American is more likely to die in his or her bathtub than from a terrorist attack, and that more people died on the roads due to increased traffic during the time after 9/11 when all flights were grounded than did in the Twin Towers attack.)</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">So, to return to the question implicit in my title, “What is mathematics used for?” <span style="color: blue;"><span lang="zxx"><u><a href="http://en.wikipedia.org/wiki/Life,_the_Universe_and_Everything">Douglas Adams</a></u></span></span> provided the answer: “Life, the universe, everything.” <span style="background-color: white; color: #222222;"><span style="font-family: inherit;">With such reach and power comes responsibility. </span></span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">FOOTNOTE: For a more personal take on the above issues, see the <span style="color: blue;"><span lang="zxx"><u><a href="http://mathtango.blogspot.co.uk/2013/06/keith-devlin-as-you-may-not-have-heard.html">interview</a></u></span></span>I did on June 21 on Shecky Riemann’s <i>Math Tango</i> blog.</div><div style="margin-bottom: 0in;"><br /></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-76479455588105813532013-07-02T13:16:00.000-04:002013-07-02T13:24:11.260-04:00“It Only Takes About 42 Minutes To Learn Algebra With Video Games”<div class="MsoNormal"><span style="font-family: inherit;">When tech folk dabble in education (and tech writers cover it), the excess of hype is sometimes matched only by their breathtaking lack of knowledge about education. Even so, the above headline to the <a href="http://www.forbes.com/sites/jordanshapiro/2013/07/01/it-only-takes-about-42-minutes-to-learn-algebra-with-video-games/">July 1 post</a> by <i>Forbes</i>contributor Jordan Shapiro must rank as one of the most stupid and ignorant statements in human history. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">It would be somewhat less ludicrous, though still open to debate, if the headline had said “learn <b><i>some</i></b> algebra.” But “algebra”? All of it?<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Almost certainly, Shapiro himself did not write the headline<span style="font-size: 12pt;">—</span>writers rarely do. In fact, the article itself is fine. I have no problem with what Shapiro wrote. But the fact that the ludicrous headline had not been changed 24 hours later indicates that <i>Forbes</i>’ editors feel happy with it. Sigh.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">What the article itself reports is that, on average, students who played a particular video game (<a href="http://www.dragonboxapp.com/">DragonBox</a>, of which more later) completed a sufficient part of it in 42 minutes. Since the game itself is based on algebraic principles, they could, therefore, be said to have engaged in algebraic thinking. (I would be inclined to say just that, though with any kind of machine learning<span style="font-size: 12pt;">—</span>and human teaching if the instructor is not paying close attention<span style="font-size: 12pt;">—</span><span style="font-family: inherit;">one sh</span>ould always be on the lookout for an instance of <a href="http://profkeithdevlin.org/tag/bennys-rules/">Benny’s Rules</a>.)<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Whether such performance in a video game justifies saying that the students <i>learned some</i> (!) <i>algebra</i> in 42 minutes depends on what metric you use to determine what learning has taken place. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Of course, if you define algebra to be (or to include) symbolic manipulation, then successful completion of any video game is not going to count as “doing algebra.” That is why I used the term “algebraic thinking” a couple of paragraphs back. (See my previous blog post <a href="http://profkeithdevlin.org/2011/11/20/what-is-algebra/">What is Algebra?</a> for a discussion of the distinction.) But is that the appropriate measure? What do we want K-12 students to learn under the title “algebra”?<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">[ASIDE: There is another definitional question as to the classification of DragonBox as a video game. Game developers have different views as to what constitutes a video game. Some would describe DagonBox as an entertaining, interactive, digital app, but would stop short at classifying it as a game.]<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Before I go any further, I should give some disclaimers. First, as readers of my blog <a href="http://profkeithdevlin.org/">profkeithdevlin.org</a> (or my book <a href="http://www.amazon.com/Mathematics-Education-New-Era-Learning/dp/1568814313/ref=sr_1_1?ie=UTF8&s=books&qid=1299701150&sr=8-1"><i>Mathematics Education for a New Era</i></a>) will be aware, I am a strong proponent of the use of video games in mathematics education. In fact, I advocate an approach to the design of math ed video games that definitely includes DragonBox. I’ve met the developer, Jean-Baptiste Huynh, and one of the co-founders of his company <a href="http://wewanttoknow.com/">WeWantToKnow</a>, and I used their game as an example in a <a href="http://www.americanscientist.org/issues/pub/the-music-of-math-games">feature article</a> on math ed video games I wrote for <i>American Scientist</i> in March of this year. I am about three-quarters of the way through the second, greatly expanded version of the game, DragonBox2. Among the designs for math ed video games that my own company, <a href="http://innertubegames.net/">InnerTube Games</a>, has been working on for several years, are a couple that have much in common with DragonBox. (We are due to release our first one, Wuzzit Trouble, this summer, but chose one based on arithmetic and number theory to be our initial release, with algebra-based games to come later.) So I am not a dispassionate outsider here.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">For his <i>Forbes</i> article, Shapiro interviewed Jean-Baptiste Huynh, and everything the DragonBox designer says, I agree with 100%. Here is my take on the benefits of playing DragonBox (besides the fact that is it fun).<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">A student who plays through the new, greatly expanded version of the game will undoubtedly engage in a substantial amount of (<b><i>contextualized</i></b>) algebraic thinking focused on the solution of linear equations in one variable. The score they obtain in the game will provide a good measure of how well they have mastered that form of thinking (i.e., solving single-variable linear equations).<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Does that mean the student can then sit down and ace a standard written algebra exam? Not at all. Even though the later stages of DragonBox and DragonBox2 involve on-screen manipulations of the standard symbolic representations of equations, the step from physically moving digital objects to manipulating symbolic expressions on a page is a much harder cognitive challenge than one might first think. The human mind simply finds it very difficult to reason in a purely abstract fashion. (In my book <a href="http://www.amazon.com/books/dp/0465016197"><i>The Math Gene</i></a>, published in 2000, I investigated the reasons for that difficulty.)<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">At issue is the notorious <a href="http://en.wikipedia.org/wiki/Transfer_of_learning">transfer problem</a>, which, roughly speaking, is the difficulty humans face in taking something that has been learned in one context and applying it in another.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">Huynh is of the opinion that it requires a human teacher to help the student take the difficult step from completion of his game to mastery of symbolic algebra, and I agree with him. I suspect that not everyone will be able to make the transition, no matter how good the teaching, but many will. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">There is certainly a lot to be gained from mastery of symbolic algebra. First of all, learning at that level of abstraction is readily applicable to any specific domain. Second, being able to reason free of the complexities of any application domain is extremely powerful. <o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">On the other hand algebra (or, more accurately, algebraic thinking) was successfully used in commerce for many hundreds of years before the modern, symbolic variety was introduced in the sixteenth century. So acquiring useful algebra skills is not totally dependent on mastery of symbolic algebra.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">A major question is, will playing DragonBox increase the likelihood that a student will be able to master symbolic algebra, compared with a student who does not have that game experience? There is good reason to assume the answer is “Yes,” but that remains to be fully tested</span><span style="font-family: "Arial","sans-serif"; font-size: 12.0pt; mso-ansi-language: EN-US; mso-bidi-font-family: Georgia; mso-bidi-font-size: 42.0pt; mso-bidi-language: AR-SA; mso-fareast-font-family: Cambria; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">—</span><span style="font-family: inherit;">something that can be done only now the game (and others like it) is out. (The analogous question remains to be answered for my own company’s forthcoming games.)<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="font-family: inherit;">My reason for suspecting that playing video games like DragonBox is highly beneficial in learning symbolic mathematics</span><span style="font-family: "Arial","sans-serif"; font-size: 12.0pt; mso-ansi-language: EN-US; mso-bidi-font-family: Georgia; mso-bidi-font-size: 42.0pt; mso-bidi-language: AR-SA; mso-fareast-font-family: Cambria; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">—</span><span style="font-family: inherit;">the kind that is tested in our school system</span><span style="font-family: "Arial","sans-serif"; font-size: 12.0pt; mso-ansi-language: EN-US; mso-bidi-font-family: Georgia; mso-bidi-font-size: 42.0pt; mso-bidi-language: AR-SA; mso-fareast-font-family: Cambria; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">—</span><span style="font-family: inherit;">is perhaps best explained by an analogy from Hollywood. In the 1984 movie <a href="http://www.imdb.com/title/tt0087538/"><i>The Karate Kid</i></a> (I can’t bring myself to watch the 2010 remake) and its sequel (KK2), martial arts instructor Mr Miyagi <a href="http://www.youtube.com/watch?v=eFK-GGG8JN0">prepares his young pupil Daniel for Karate tournaments</a> by getting him to polish a car, sand a floor, catch a fly with chopsticks, and paint a fence, all of which develop the reflexes and muscle memory required for key Karate moves, which Daniel uses to great effect later in the movies.</span></div><div class="MsoNormal"><span style="font-family: inherit;"><br /></span></div><div class="MsoNormal"><span style="font-family: inherit;">True, this is not sound educational theory, though many teachers (and most athletic coaches) adopt a similar approach. (This is a blog, remember, not a research journal.) But until we have something more concrete, the analogy works for me. Indeed, I am betting my company on it</span><span style="font-family: "Arial","sans-serif"; font-size: 12.0pt; mso-ansi-language: EN-US; mso-bidi-font-family: Georgia; mso-bidi-font-size: 42.0pt; mso-bidi-language: AR-SA; mso-fareast-font-family: Cambria; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">—</span><span style="font-family: inherit;">as is Jean-Baptiste Huynh.</span></div><div class="MsoNormal"><o:p></o:p></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-20433042835393685422013-06-03T07:18:00.000-04:002013-06-03T08:58:41.958-04:00 Will Cantor’s Paradise Ever Be of Practical Use?We really have no way of knowing what early humans thought when they gazed up at the sky. Since everyday practical experience is, by definition, limited to a very small region of space and time, it requires considerable cognitive sophistication to conceive of something – say the night sky – “going on for ever,” let alone to ponder whether that means it is “infinite,” or indeed what “infinite” actually means.<br /><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">What we do know is that the ancient Greeks made what may have been the first substantial attempt to analyze the notion of infinity, with Zeno of Elea (ca 490-430 BCE) of particular note for his discussion of a number of (seeming) paradoxes that arise from the assumption that space and time are (or are not) infinitely divisible.</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Archimedes’ (ca 287-112 BCE) calculations of areas and volumes made implicit <span style="color: black;">use of infinity, and from today’s perspective can be recognized as the forerunner of integral calculus. </span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">Skillful formal – though by modern standards not rigorous – use of the infinitely large and the infinitely small was made by Isaac Newton and Gottfried Leibniz in their development of modern infinitesimal calculus in the seventeenth century, though it was not until the nineteenth century when </span><span style="color: black;"><a href="http://en.wikipedia.org/wiki/Bernard_Bolzano">Bernard Bolzano</a>, <a href="http://en.wikipedia.org/wiki/Augustin-Louis_Cauchy">Augustin-Louis Cauchy</a>, and <a href="http://en.wikipedia.org/wiki/Karl_Weierstrass">Karl Weierstrass</a> finessed the lurking problems of infinity by means of the famous (and for many a first-year mathematics major, infamous) epsilon-delta definitions of limits and continuity.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">But none of these developments was about infinity as an </span><span style="color: black;"><i>entity</i></span><span style="color: black;">; the focus rather was on the unending nature of certain processes, starting with counting. It was</span><span style="color: black;"> </span>Georg Cantor (1845 – 1918) who really tackled infinity head on. His proof that the set of real numbers cannot be put into one-one correspondence with the natural numbers, and hence is of a larger order of infinitude, led to a series of papers, published in a remarkable ten-year period between 1874 and 1884, that formed the basis for modern abstract set theory, including the development of a fully formed arithmetical theory of infinite numbers (or “cardinals”).</div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;">Reactions to Cantor’s revolutionary new ideas ranged from outraged condemnation to fulsome praise.<span style="color: black;">Henri</span> Poincaré called Cantor’s work a “grave disease” that threatened to infect mathematics, and Leopold Kronecker described Cantor as a “scientific charlatan” and a “corrupter of youth.” Ludwig Wittgenstein, writing long after Cantor's death, complained that mathematics had become “ridden through and through with the pernicious idioms of set theory,” a theory he dismissed as “utter nonsense,” “laughable,” and “wrong.” </div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">At the other end of the spectrum, in 1904, in the UK the <a href="http://en.wikipedia.org/wiki/Royal_Society">Royal Society</a> awarded Cantor its highest award, the <a href="http://en.wikipedia.org/wiki/Sylvester_Medal">Sylvester Medal</a>, and in Germany <a href="http://en.wikipedia.org/wiki/David_Hilbert">David Hilbert</a> declared that “No one shall expel us from the Paradise that Cantor has created.”</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">Having devoted the early part of my professional career to work in (infinitary) set theory, starting with my Ph.D. in “large cardinal theory,” completed in 1971, and moving on to work on alternative universes of sets (a particularly hot topic after Paul Cohen’s introduction of the <a href="http://en.wikipedia.org/wiki/Forcing_(mathematics)">method of forcing</a> </span><span style="color: black;">in 1963), in the early 1980s my interests started to shift elsewhere, to questions about information, communication, and human reasoning.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">I found myself temporarily back in the world of set theory and the arithmetic of infinite numbers recently, when I was approached by the organizers of the </span><span style="color: navy;"><span lang="zxx"><a href="http://worldsciencefestival.com/" target="_blank">World Science Festival</a></span></span><span style="color: black;"> to moderate a <a href="http://worldsciencefestival.com/events/infinity">panel discussion on the topic of infinity</a></span><span style="color: black;"> and a more in-depth <a href="http://worldsciencefestival.com/events/the_future_of_infinity">follow-up</a></span><span style="color: black;"> the following day.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">Both discussions raised the question as to whether study of infinity – in particular the hierarchy of larger infinities that Cantor bequeathed to us – would ever have any practical applications. As panelist Hugh Woodin remarked at one point in the discussion, it is a foolish mathematician who declares that a particular piece of mathematics will not find applications. For instance, G. H. Hardy’s famous statement (in his book </span><span style="color: black;"><i>A Mathematician’s Apology</i></span><span style="color: black;">) that his work in number theory would never find practical application, proved to be spectacularly wrong less than a century later, when number theory became the foundation for internet security.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">Hardy’s observation was based on his familiarity of the world he lived in, a world in which the World Wide Web was not even a dream. Today, we cannot know what the world of tomorrow will look like. On the other hand, whatever our children and grandchildren will take for granted, their world will surely be finite, which makes it unlikely that Cantor’s theory – and the almost a century of development in set theory since then – will have practical use. </span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">Or does it? What about calculus? Infinitesimal (!) calculus not only has applications in the modern world, but much of the science, technology, medicine, and even financial structure the underpins our world depends on calculus for its very existence. Applications don’t get more real than that. </span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">True, but the dependence on infinities you find in calculus is essentially asymptotic. What really drives calculus is the unending nature of certain processes on the natural numbers. Talk of “infinitely large” or “infinitely small” is little more than a manner of speaking. Indeed, the epsilon-delta definitions (which do not involve infinities or infinitesimals) are a way to formalize that manner of speaking, effectively eliminating any actual infinite or infinitesimal quantities.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">In contrast, much of the work on infinity (more precisely, infinities) carried out in the second half of the twentieth century (when I was working in that area) focused on properties of sets that made their cardinalities super-infinities of different orders: inaccessible cardinals, Ramsey cardinals, measurable cardinals, compact cardinals, supercompact cardinals, Woodin cardinals, and so on. Infinities which dwarfed into invisibility the puny cardinality of the set of natural numbers. Indeed, each one in that sequence dwarfed all its predecessors into invisibility. How could that work find an application?</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">I’ll lay my cards on the table. I think the chances are that it won’t. But I don’t think it is impossible. Indeed, I began to suspect a possible application in the very domain I worked in after I left set theory.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">[This may of course be nothing more than a reflection of having at my disposal a large hammer which made everything look a bit like a nail. But let’s press on.]</span></div><div style="margin-bottom: 0in;"><span style="color: black;"><br /></span></div><div style="margin-bottom: 0in;"><span style="color: black;"> </span></div><div style="margin-bottom: 0in;"><span style="color: black;">The post 9/11 world saw me involved in a series of Defense Department projects the first being improving intelligence analysis (and the others essentially variants of that).</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">In today’s information rich world, the major nations can be assumed to have access to all the information they need to predict (and hopefully thence prevent) the majority of terrorist attacks. The trouble is, the few data points which must be identified and connected together to determine the likelihood of a future attack are just a tiny few in an overwhelming ocean of data. Even in the era of cloud computing, identifying the key information is analogous to using the naked eye to find a handful of proverbial needles in a non-proverbial field of haystacks.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">To all intents and purposes, the available data is infinite. The only hope is to impose some structure on the data that makes it possible for humans and computers to work together on it, narrowing down the focus to the regions more likely to be of significance. Though modern computing systems can sift through massive (finite) amounts of data in a relatively short time, they need to be programmed, and writing those programs (at least, some kinds of them) will require some structure on those large sets of data. A possible place to find the appropriate structure(s) is infinitary set theory. In other words, to develop the appropriate structures, assume the data is infinite. View the infinite as a theoretical simplification of the very large finite. (Economists sometimes make a similar simplifying assumption about economies.)</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">Do I think this is likely? Frankly, no. But then, neither could Hardy conceive of any practical application of his work in number theory. [Incidentally, like Hardy, I don’t think mathematics needs applications to justify itself. It’s just that the question of application is what this article is about!]</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">The discussion about large cardinals you will find in those panel discussions at the World Science Festival might seem impossibly abstract and far removed from the everyday world. Indeed, it is. But the questions being discussed all resulted from a process of rigorous, logical investigation that arose directly from late nineteenth century attempts to understand heat flow. History tells us that what begins in the real world, very often ends up being used in the real world.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">Prediction is hard, particularly about the future.</span></div><div style="margin-bottom: 0in;"><br /></div><div style="margin-bottom: 0in;"><span style="color: black;">Incidentally, how did I end up working on a project for the DoD? They asked me. I might not be the only person to speculate about a possible use of Cantor’s paradise. This is your taxpayer dollars at work.</span></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-34265244004292926492013-05-01T06:00:00.000-04:002013-05-02T06:36:15.975-04:00The Mother of All NCTM Addresses<div style="text-align: left;"><span style="font-family: Times, Times New Roman, serif;">This month’s column is short, but I am asking you to set aside 51 minutes and 36 seconds to watch the embedded video. It is a recording of the <span style="color: black;">Iris M. Carl Equity Address given on Friday April 19 at this year’s </span>NCTM Annual Conference in Denver, Colorado. The title of the talk is “<span style="color: black;">Keeping Our Eyes on the Prize” and the speaker is Uri Treisman, </span><span style="color: #262626;">professor of mathematics and of public affairs, and director of the Charles A. Dana Center, at the University of Texas at Austin</span><span style="color: black;">.</span><br /></span></div><div style="margin-bottom: 0in;"><div style="text-align: left;"><span style="font-family: Times, Times New Roman, serif;"><br /></span></div></div><div style="margin-bottom: 0in;"><div style="text-align: left;"><span style="color: black; font-family: Times, Times New Roman, serif;">I was not able to be at NCTM, but on the recommendation of several colleagues, I watched the YouTube video. I simply cannot write a column on mathematics or mathematics education in the same month as Treisman’s immensely more important, profound—and powerfully articulated—words became part of mathematics education history. As a community, we now have our own “I have a dream” speech. Thank you, Uri.</span></div><div style="text-align: left;"><br /></div></div><div style="text-align: center;"><iframe allowtransparency="true" class="wistia_embed" frameborder="0" height="243" name="wistia_embed" scrolling="no" src="http://fast.wistia.net/embed/iframe/wm08r9ly6w?controlsVisibleOnLoad=true&playButton=false&version=v1&videoHeight=243&videoWidth=320&volumeControl=true" width="320"></iframe><br /><br /><div style="text-align: left;"><span style="background-color: white; color: #222222;"><span style="font-family: Times, Times New Roman, serif;">PDFs of Treisman's presentation slides are available <a href="http://www.nctm.org/uploadedFiles/Conferences/Annual_Meetings/2013-Denver/-NCTM%20Iris%20Carl%20Talk%204-19-13.pdf" target="_blank">here</a>.</span></span></div></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-50126297818774847672013-04-01T08:55:00.004-04:002013-05-01T09:47:34.773-04:00Only in Silicon Valley<span style="background-color: white; color: #222222;"><span style="font-family: Times, Times New Roman, serif;">ADDED MAY 1: NOTE THAT THIS COLUMN WAS POSTED ON APRIL 1, "ALL FOOLS DAY" IN THE USA AND SEVERAL OTHER COUNTRIES.</span></span><br /><div class="MsoNormal"><br />One of the benefits of being at a university like Stanford is that we occasionally get the opportunity to see up close the emergence of an amazing mathematical talent<span style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; line-height: 107%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">—</span>someone who may turn out to be the next Euler or Gauss. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Just over 18 months ago, Avril Wan was, to all appearances, just another bright fourteen-year-old living in Taiwan, where her father Yewful Wan runs a large shipping company and her Welsh-born mother Melanie Wan is a university mathematics professor (and a former student of <a href="https://www.dpmms.cam.ac.uk/~wtg10/">Timothy Gowers</a> in Cambridge).<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Then, in September 2011, Stanford computer science professor Sebastian Thrun and Google researcher Peter Norvig offered what turned out to be the first of what is now a flood of Massively Open Online Courses (MOOCs), which make advanced university courses available to the entire world over the Internet. Ms. Wan enrolled for that first MOOC, in artificial intelligence, and was the only student to score a perfect 100% for the course.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">When initial investigations made it clear that Ms. Wan’s performance was legitimate, Thrun moved quickly, and arranged for Stanford to offer her a place in Stanford’s famed <a href="http://symsys.stanford.edu/">Symbolic Systems Program</a> (which has produced a whole string of graduates who have founded and led successful Silicon Valley companies, such as Reid Hoffman, who founded LinkedIn, and Marissa Meyer, an early employee of Google and the new<span style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; line-height: 107%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">—</span>and controversial<span style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; line-height: 107%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">—</span>CEO of Yahoo!).<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">By the time Wan arrived at Stanford, Thrun had left to form <a href="https://www.udacity.com/">Udacity</a>, a Silicon Valley start-up offering free online courses to the world, and the newly arrived student, who had just turned 15 (and was accompanied by her mother), was assigned to the educational care of another famous Stanford mathematics professor, <a href="http://www-stat.stanford.edu/~cgates/PERSI/">Persi Diaconis</a>, known for his ability to see familiar problems in novel ways. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">In late spring of 2012, there was a buzz across the Palo Alto campus when it seemed that, under minimal guidance from Diaconis, the young Ms. Wan had solved the notorious <a href="http://en.wikipedia.org/wiki/P_versus_NP_problem">P = NP problem</a>, but <a href="http://www.math.ucsd.edu/~fan/ron/">Ron Graham</a> of the University of California at San Diego quickly found an error, pointing out that she had implicitly assumed the existence of a complete, two-valued measure on the power set of the natural numbers<span style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; line-height: 107%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">—</span>a question first raised by the famous (Second World) Wartime mathematician <a href="http://en.wikipedia.org/wiki/Stanislaw_Ulam">Stan Ulam</a>.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Meanwhile, Ms. Wan’s mathematics blog had started to attract attention back in her home country, making her somewhat of a Taiwan celebrity. In particular, motivational videos she had posted on YouTube to encourage young Taiwanese girls to study mathematics, eventually came to the attention of News Corporation’s Rupert Murdoch, who pledged $5M to make her videos available throughout the developing world. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">But then, online tech journalist <a href="http://dangillmor.com/">Dan Gillmor</a> posted an article pointing out that Murdoch’s funding was contingent on the distribution being restricted to streaming to tablets supplied by his own, for-profit company <a href="http://www.amplify.com/">Amplify</a>. If so, that would surely have killed the deal, since Ms. Wan recognizes the value of free educational resources to the development of the less affluent countries of the world.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">At that point, events started to unfold at the kind of breakneck speed that only happens in Silicon Valley. Ms. Wan, still just 15 years old, remember, and technically without even a high school diploma, found herself inside the Palo Alto offices of the famed venture capital company <a href="http://www.greylock.com/">Greylock Partners</a>, which was willing to commit $100M to fund the establishment of a global, free, online mathematics education platform, tentatively called “Wan World.”<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">With Greylock having been early stage funders of some of the most successful start-up companies in recent years, most of which required several years before anyone had the faintest idea how they would make money, that interest was all it took to unleash the floodgates. Within a few days, Ms. Wan (or rather, the group of advisers her father quickly assembled to cope with the interest) had been approached by Apple, Google, and Facebook, each of which wanted to develop the platform on which Wan World would run, and by McGraw Hill, Pearson Education, and Amazon, who wanted to own the content.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Meanwhile, despite all this frenzy, Ms. Wan herself seems remarkably unfazed by the sudden changes in her life. Speaking to an unusually full room in a recent meeting of Stanford’s <a href="http://edf.stanford.edu/">Education’s Digital Future</a> lecture/discussion series (which is where I first met her), she concluded her presentation by admitting to her fellow students, “Like you, right now, I just want to graduate.” <o:p></o:p></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0tag:blogger.com,1999:blog-2516188730140164076.post-84111153250280796772013-03-01T09:04:00.000-05:002013-03-01T09:04:08.145-05:00Can we make constructive use of machine-graded, multiple-choice questions in university mathematics education?<br /><div class="MsoNormal">A good metaphor for the current state of MOOC education is provided by <a href="http://www.youtube.com/watch?v=13qeX98tAS8">this historical video</a>. But when you look at those images, please remember <a href="http://www.youtube.com/watch?v=sTBIr65cL_E">what those events led to</a>. Unless you are able to keep that history in mind, you should not at this stage get into the MOOC business. For <a href="http://en.wikipedia.org/wiki/Here_be_dragons">there be only dragons</a>.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">With the second edition of my Stanford MOOC <a href="https://www.coursera.org/course/maththink">Introduction to Mathematical Thinking</a> starting this weekend on Coursera, I have once again been wrestling with the question of the degree to which good, effective mathematics learning can be achieved at scale, over the Internet.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Once I had made the decision to try to take (elements of) my 35-year-old mathematics transition course into the then emerging MOOC format<span style="font-family: "Arial","sans-serif"; font-size: 12.0pt; mso-ansi-language: EN-US; mso-bidi-font-family: "Times New Roman"; mso-bidi-font-size: 10.0pt; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Cambria; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">—</span>less than a year ago!<span style="font-family: "Arial","sans-serif"; font-size: 12.0pt; mso-ansi-language: EN-US; mso-bidi-font-family: "Times New Roman"; mso-bidi-font-size: 10.0pt; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Cambria; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">—</span>I was immediately brought face-to-face with the necessity of making use of two educational devices I had loathed (and never used) throughout my entire career in higher education:<o:p></o:p></div><div class="MsoNormal"></div><ol><li>machine-graded pop quizzes</li><li>machine-graded multiple-choice questions</li></ol><div class="MsoNormal">For MAA readers, I don’t think I need to explain my dislike for either of these über-simplistic devices, which can surely be justified in a regular classroom only in terms of making life easier for the instructor.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Simply putting a class online does not require the use of either device, of course. Technologies such as video conferencing and screen sharing can make learning at a distance almost as good as traditional classroom learning, and in some circumstances can make it better in some respects. But making a class available to <i>tens of thousands</i> of students online changes everything. With such large numbers, the “class” dynamics change dramatically. But it’s not all for the worse.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">The first thing to realize is that a MOOC is in many ways like radio or TV. Though both of those familiar features of modern life are referred to as “mass media,” they are in fact highly individual. The newsreader on radio or TV is not addressing a large audience; she or he is talking to millions of <i>single individuals</i>. The secret to being good on the radio or TV is to forget the millions and think of just one (generic) person. After all, the listener or viewer is not in a room with millions of other people; in fact, if the broadcast is successful, that listener or viewer is cognitively in a room <i>with just the presenter</i>. The really successful radio and TV newsreaders and presenters are the ones who can do that really well. They create that sense that they are talking just to <i>You</i>.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">In my own case, I already knew that from many years of occasional media work, but I think all MOOC instructors come to that realization very quickly. When your voice, with or without your face, is in someone’s living room, there is a direct human connection that in important ways is far more intimate than is possible in a lecture hall filled with anything more than a handful of students.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Once you realize this feature of the MOOC medium, the underlying pedagogic model is obvious. It’s one-on-one teaching/learning<span style="font-family: "Arial","sans-serif"; font-size: 12.0pt; mso-ansi-language: EN-US; mso-bidi-font-family: "Times New Roman"; mso-bidi-font-size: 10.0pt; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Cambria; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">—</span>something that in the traditional academy is (of necessity) reserved only for doctoral students.<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">At which point, the appropriate use of both pop quizzes and multiple-choice questions starts to look feasible. (They ought to; doctoral advisers use both extensively, and to great positive effect, though they do not refer to them as such, and there is no machine-grading!)<o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Of course, in a MOOC it remains the case that the student cannot communicate directly with the professor, nor can the professor see and comment on an individual student’s work. That means two further techniques have to be used as well:</div><div class="MsoNormal"></div><ol start="3"><li>peer tutoring</li><li>peer evaluation </li></ol><div class="MsoNormal">In the first version of my MOOC, last September, I built the course around the doctoral-student education model, deliberately setting out to create the experience of a student sitting alongside me at my desk. (There is a low resolution example <a href="http://www.youtube.com/watch?v=AbZgIj4piv0">here</a>.) <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">But as a result of a career-long dislike of the first two and a deep suspicion of the fourth, I used all but the third of those auxiliary devices reluctantly and as little as possible. (The one I did embrace, peer tutoring, did not work well the way I set it up. See below for details of Attempt Two.) <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">Because of my caution, I think I avoided a fate reminiscent of NASA’s first attempts to launch a rocket into space. But that was a first, exploratory experience, and I wanted to live to try again. This time around, based on what I learned, I am going to use all four much more aggressively, but in ways I think might work. <o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal">I’ll be describing how I’ll be using them in a series of posts to my blog <a href="http://mooctalk.org/">MOOCtalk.org</a>. For a brief<span style="font-family: Arial, sans-serif; font-size: 12pt;">—</span>and decidedly limited<span style="font-family: Arial, sans-serif; font-size: 12pt;">—</span>foretaste, check out <a href="http://www.youtube.com/watch?v=vpF5e9J05oQ">this video excerpt</a> of a conversation my MOOC TA Paul Franz and I had recently with radio and TV personality Angie Coiro, <span style="color: #262626; mso-bidi-font-family: "Helvetica Neue"; mso-bidi-font-size: 14.0pt;">host of the syndicated radio and television interview show </span><a href="http://lftlc.com/"><i>In Deep</i></a><span style="color: #262626; mso-bidi-font-family: "Helvetica Neue"; mso-bidi-font-size: 14.0pt;">.</span><br /><o:p></o:p></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #262626; mso-bidi-font-family: "Helvetica Neue"; mso-bidi-font-size: 14.0pt;">The goal of Version 2 of the course is not to reach the Moon. Chances are high that we’ll crash and burn. The goal is to at least get off the ground before we do, and, if we are lucky, maybe even reach the upper atmosphere. For sure, there will still be a long way to go.<o:p></o:p></span></div><div class="MsoNormal"><br /></div><div class="MsoNormal"><span style="color: #262626; mso-bidi-font-family: "Helvetica Neue"; mso-bidi-font-size: 14.0pt;">If you want to live dangerously and be part of this huge experiment, and if you have a Ph.D. (or pending Ph.D.) in mathematics and several years of college teaching behind you, I am still looking for well qualified volunteers to act as “Community TAs” for the course, to answer students' questions on the course discussion forums. So far I have 14 volunteers, </span>comprising 5 college professors, 3 Ph.D. students, 3 individuals currently working in the software industry, a K-12 education consultant, a research laboratory scientist, and a stock analyst. If you want to volunteer, and have the requisite experience, please drop me an email at <a href="mailto:devlin@stanford.edu">devlin@stanford.edu</a>. (There is no payment for doing this<span style="font-family: "Arial","sans-serif"; font-size: 12.0pt; mso-ansi-language: EN-US; mso-bidi-font-family: "Times New Roman"; mso-bidi-font-size: 10.0pt; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Cambria; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">—</span>that includes me!) But being part of a large and truly global community, who come together for several weeks for the sole purpose of learning how to think mathematically (the course carries no college credit), is truly a wonderful experience.<o:p></o:p></div>Mathematical Association of Americahttp://www.blogger.com/profile/10559021045290192742noreply@blogger.com0