Links for November 30

Stian Haklev on Starting data analysis/wrangling with R: Things I wish I’d been told.

Zulko on Things you can do with Python and POV-Ray (a raytracing engine).

Sanjoy Mahajan has a new book out, The Art of Insight in Science and Engineering” Mastering Complexity. This looks like it could be thought of a more science- or engineering-themed sequel to his Street-Fighting Mathematics.

Nigel Stanford’s Cymatics “is the science of visualizing audio frequencies.”

Does teaching gamblers about probability make them less likely to gamble? (Yes.)

FiveThirtyEight has a nerd holiday gift guide.

From Katie Steckles at the Aperiodical, Twitter’s favorite fictional mathematicians.

Parents strongly cautioned for advanced math

From A. O. Scott’s review of The Imitation Game, the new Alan Turing biopic:

“The Imitation Game” is rated PG-13 (Parents strongly cautioned). Illicit sex, cataclysmic violence and advanced math, most of it mentioned rather than shown.

First, advanced math is reason for caution? Um, no.

Second, what’s the difference between “mentioning” and “showing” mathematics anyway? This seems to be connected to the philosophical use-mention distinction, Godel numbering, and so on, but I doubt that Scott is trying to make a metamathematical point. This may just mean that people in the movie don’t sit around scribbling on pieces of paper but rather talk about the fact that they have done so, which is good, because I’ve watched people do math and there’s really nothing to see.

Thanksgiving power law

In honor of Thanksgiving: take a look at Niall MacKay’s paper Of bombs and boats and mice and men: a random tour through some scaling laws.

I mention this because one of the scaling laws there is the time it takes to roast a turkey – you can work out from dimensional analysis that roasting time is proportional to the two-thirds power of mass. Specifically, the thermal diffusivity κ of meat (or any other substance) – that’s the constant in the heat equation – has dimensions of length squared over time. Since the only relevant parameter is the length of the turkey l, roasting time must be proportional to l2/κ. But assuming a spherical turkey, length is proportional to the cube root of mass, giving the two-thirds law.

Happy Thanksgiving! And for my readers abroad, happy Thursday.

Links for November 23

Mona Chalabi and Andrew Flowers figure out the most common name in America, using some data by Lee Hartman to correct for the fact that first name and last name are not independent, but tend to cluster based on ethnicity. A fun fact: apparently people avoid alliteration. Does this extend to martial name-changing? For example, say my wife’s first name starts with an L, as does my last name; does that make her less likely to have changed her name upon marriage? She didn’t, but I can’t attribute that to the alliteration.

From Jawbone via the Atlantic, people don’t exercise when it’s cold. (A bit less obvious in the data is that they don’t exercise when it’s hot, either.)

David Mimno at Cornell has a fun word similarity tool based on a corpus of pre-1923 books.

Michael Harris at Slate writes about the Breakthrough Prize, which are trying to be the “Oscars of science”. He’s got a book coming out called Mathematics Without Apologies, which is at least the second in a line of titles riffing on A Mathematician’s Apology, after The Unapologetic Mathematician. (And don’t forget Second-Rate Minds (expositors, according to Hardy).

Tim Hersterberg at Google has written on What Teachers Should Know about the Bootstrap: Resampling in the Undergraduate Statistics Curriculum

From Todd W. Schneider (who’s on fire lately): the Reddit front page is not a meritocracy. (Disclaimer: Schneider, or someone with his same name and similar demographic history, was a year behind me in high school.)

Christian Perfect linked to a short documentary, Logically Policed by Damiano Petrucci, about mathematicians.

Rob Hyndman on visualization of probabilistic forecasts.

Mark Jason Dominus on teaching his daughter algebra.

Emilia Petrisor writes (with code – an iPython notebook) on domain coloring as a way of visualizing complex-valued functions

Mike of mikemathspage and his kids made some videos on the Collatz conjecture and a variation on it due to Conway. (The Conway variation is in his paper “On Unsettleable Arithmetic Problems”.)

From Pip ( = Dick Lipton + Ken Regan) at Gödel’s Lost Letter and P = NP: two vs. three. Why is two so special?

Rasmus Bååth and Christian Robert wrote a A Brief Review of All Comic Books Teaching Statistics in Chance.

There’s a second edition of Skiena’s Algorithm Design Manual.

A temperature puzzle

Last Friday morning (the 14th) it was unseasonably cold in Atlanta. On the way to work I noticed my car’s display giving the following temperature readings: 28, 30, 32, 34, 36 – all in Fahrenheit. It somehow knew to avoid the odd numbers.

But in the evening of the same day it read 39, 41, and 43. Now it knew how to avoid the even numbers.

I watched a little more closely for a while – on a trip on Sunday morning it read 46, and then 48. On Monday morning, 50, 52, and 54. Even again.

A puzzle for readers: what’s going on? (I know the answer.)

Links for November 16

When you are listening to corn pop, are you listening to the Central Limit Theorem?

12 Scientific Sculptures: Intangible Data in Physical Form

Kokichi Sugihara uses computation to make three-dimensional illusion

Markov Chains vs Simulation: Flipping a Million Little Coins.

Brian Hayes on lopsided precinct-by-precinct voting results.

Simon Singh on Homer’s Last Theorem. I’m currently enjoying his book The Simpsons and Their Mathematical Secrets.
how the Google priority inbox works

Terry Tao announces his winter analytic prime number theory course, the announcement doubling as an introduction to why one might be interested in such a subject and the techniques used in it.

Spliddit is a new website by Ariel Procaccia and Joanthan Goldman which implements algorithms for splitting rent, dividing goods, and sharing credit. They claim a twofold mission: “To provide easy access to carefully designed fair division methods, thereby making the world a bit fairer. To communicate to the public the beauty and value of theoretical research in computer science, mathematics, and economics, from an unusual perspective.”

From Numberphile, how math goes into making Pixar’s movies.