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Dr. Keith Devlin
Dr Keith Devlin is a mathematician at Stanford University in Palo Alto, Calif., where he directs the H-STAR institute, which he co-founded in 2006. He is also a co-founder of the educational technology company BrainQuake. He blogs regularly for mathematically-inclined readers at and, and his MOOC Introduction to Mathematical Thinking (the world's first-ever mathematical thinking MOOC) will be offered for the sixth time in February. He is known to millions of NPR listeners as The Math Guy on Weekend Edition with Scott Simon.

Entries by Dr. Keith Devlin

What Does The UK Brexit Math Really Tell Us?

(0) Comments | Posted July 12, 2016 | 4:02 PM

The recent (and in many respects ongoing) Brexit vote in the United Kingdom provides a superb example of poor use of mathematics. Regardless of your views on the desirability or otherwise of the UK remaining a member of the European Community (an issue on which this article is agnostic), for...

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Andrew Hacker and the Case for and Against Algebra

(4) Comments | Posted February 27, 2016 | 10:59 PM

March 1 saw the publication of the book The Math Myth: And Other STEM Delusions, by Andrew Hacker. I have published my review of that book in Devlin's Angle, my regular column for the Mathematical Association of America. In this article, I'll set the scene by describing an...

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Movie Review: Love and Competitive Math

(0) Comments | Posted September 2, 2015 | 4:38 PM

Chances are, you never knew there was an annual International Mathematical Olympiad (IMO), where nations around the world (over 100 in recent years) send a team of six pre-collegiate mathematics students to compete for individual and team medals.

The IMO, held this year in Chiang Mai, Thailand in July, complete...

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Edtech Investment Is at Record Levels -- Where Is All the Money Going?

(0) Comments | Posted January 6, 2015 | 4:04 PM

US educational technology companies raised a total of $1.36 billion in 2014, according to a recent report in EdSurge. But very little of that technology is likely to end up in the K-12 classroom as part of the teaching-learning process that education is supposed to be about. Why...

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Let's Get Real About Math Word Problems

(0) Comments | Posted October 1, 2014 | 1:36 PM

OK, here is a math word problem for you: How many different ways can you arrange five keys on a circular ring?

Before you read any further, you might want to try to solve it.

This very problem came up on my Twitter feed some while ago. (I follow...

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A Common Core Math Problem With a Hint

(73) Comments | Posted May 22, 2014 | 9:31 AM

"Teaching math according to the Common Core principles means today's students could master all the mathematical thinking ability they need for college and life by focusing only on elementary arithmetic and algebra."

The Common Core State Standards (CCSS) for mathematics continue to generate a lot of online debate. As a...

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Coming to Terms With Keurig Coffeemaker Guilt

(0) Comments | Posted February 10, 2014 | 9:34 AM

Okay, Keurig, you win. Late last night I finally admitted to myself that the convenience of pod-based coffee makers outweighs the loss of flavor and aroma you encounter when you stop preparing coffee the old way.

We mathematicians are one of many social groups who tend to make a big...

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Love and Math: A Modern Russian's Lara Poem

(0) Comments | Posted January 15, 2014 | 4:47 PM

Edward Frenkel's book Love and Math is, quite simply, a love story, one man's declaration of his love for, and romantic description of, the mistress that destiny assigned him. If I had to sum up the book in one word, that word would be passion. The romantic prose, at times...

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Why MOOCs May Still Be Silicon Valley's Next Grand Challenge

(2) Comments | Posted November 18, 2013 | 10:23 AM

The recent announcement from Sebastian Thrun, founder of MOOC provider Udacity, that he is abandoning his original "teach the world" educational vision and concentrating on corporate training, has been seen by many as marking the beginning of the end of what just a year was being touted as...

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MOOC Mania Meets the Sober Reality of Education

(17) Comments | Posted August 19, 2013 | 3:31 PM

Politicians who saw MOOCs as a means to cut the cost of higher education are having to think again after two high-profile initiatives in California recently came to a crashing halt.

The more publicized trainwreck, though arguably the lesser significant of the two, was the partnership between San Jose State...

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Will We Give Up Our Constitutional Freedoms Because We Can't Count?

(2) Comments | Posted June 11, 2013 | 5:05 PM

In many ways, the recent revelation of the NSA's secret PRISM domestic spying program was reminiscent of Lance Armstrong's appearance on Oprah, where he admitted to doping throughout his cycling career. In neither case was any reflective person shocked. We'd always suspected as much. But even strong suspicion is not...

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Can Massive Open Online Courses Make Up for an Outdated K-12 Education System?

(1) Comments | Posted March 27, 2013 | 2:58 PM

Overall, schools seem to be doing a poor job of preparing today's children for the world they will live in. And I'm not just talking about American schools. The problem seems to be almost global. The evidence for this hits me square in the eyes each day when I log...

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MOOCs and the Myths of Dropout Rates and Certification

(23) Comments | Posted March 2, 2013 | 1:11 PM

When the second iteration of my free mathematics MOOC starts this weekend, I anticipate at least 30,000 students will sign up. Not as many as the 65,000 I got last year, when it had novelty value -- and a lot less competition! -- but still a substantial number.


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Racial Slurs Against a Brit? You're Kidding!

(1) Comments | Posted September 2, 2012 | 4:06 PM

I suspect it's pretty rare for an expat Brit to be the object of racial denigration, but after living in the US for twenty-five years and being a citizen for over fifteen, it finally happened to me this past week. Considering the experiences of other immigrants, I am clearly lucky...

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The Curious Use of Language in the Lance Armstrong Decision

(51) Comments | Posted August 27, 2012 | 3:37 PM

Did Lance Armstrong dope or use blood transfusions during his professional cycling career? I have no idea. Nor, it appears, does anyone else except for Lance and perhaps a few members of his team. But as a mathematician with expertise in the use of language in reasoning, I find the...

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Does Touch Get the Math Right?

(5) Comments | Posted March 26, 2012 | 10:38 AM

The new Fox TV series Touch, starring Kiefer Sutherland, has as one of its central characters a mathematically gifted, autistic, 11-year-old child Jake, played by David Mazouz. How accurate is the portrayal of mathematics in the show? Based on the first episode, the answer is, "Not very." (The...

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All the Math Taught at University Can Be Outsourced. What Now?

(56) Comments | Posted March 23, 2012 | 11:04 AM

"Those jobs are not coming back." That was the answer Steve Jobs reportedly gave to Barack Obama in February of last year, when the president asked him if it was possible for Apple to bring back the manufacture of some of its products to the United States.


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Khan Academy: Good, Bad, or Ugly?

(42) Comments | Posted March 20, 2012 | 11:56 AM

CBS's 60 Minutes segment on Khan Academy recently, opened with former hedge fund manager turned world-educator Salman Khan riding home on a bicycle, evoking (I suspect deliberately on the part of 60 Minutes) one of America's most cherished images: the lone stranger who rides into town and fixes...

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How do you read "-3"?

(2) Comments | Posted March 12, 2012 | 5:15 PM

How do you say "-3": "negative three" or "minus three"?

It sounds like a simple enough question. But a recent group discussion on LinkedIn generated over 60 contributions when I last checked. People seem to have very clear preferences as to what is "right." Unfortunately, those preferences differ.


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Silicon Valley: Failing the Way to Better Education

(0) Comments | Posted March 5, 2012 | 5:00 PM

If there is one thing Silicon Valley knows how to do, it is fail. We do it all the time, and that is the secret of our famed success.

To the rest of the world, the Valley is a place of enormous commercial successes in the tech world: HP, Intel,...

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