Monthly Archives: January 2011

Daily tips update

RegexTip, a Twitter account for learning regular expressions, starts over today with basics and will progress to more advanced properties over time. SansMouse, an account for Windows keyboard shortcuts, started over with basics two weeks ago. Both RegexTip and SansMouse

Tagged with:
Posted in Uncategorized

Scientific results fading over time

A recent article in The New Yorker gives numerous examples of scientific results fading over time. Effects that were large when first measured become smaller in subsequent studies. Firmly established facts become doubtful. It’s as if scientific laws are being

Tagged with: , ,
Posted in Science, Statistics

Weekend miscellany

Music Sacred classical music Free Bach organ recordings Programming Why you can’t hire great Perl programmers 65 attempts at resolving P versus NP Math Math blogs: MathBlogging.org Dynamical systems on a plane Exotic spheres ESP and statistics Sums of cubes

Posted in Uncategorized

Your job is trivial. (But I couldn't do it.)

Ever had a conversation that could be summarized like this? Your job is trivial. (But I can’t do it.) This happens in every profession. Everyone’s job has difficulties that outsiders dismiss. I’ve seen it in everything I’ve done, but especially

Posted in Software development

How long computer operations take

The following table is from Peter Norvig’s essay Teach Yourself Programming in Ten Years. All times are in units of nanoseconds. execute typical instruction 1 fetch from L1 cache memory 0.5 branch misprediction 5 fetch from L2 cache memory 7

Tagged with:
Posted in Computing, Software development

Occam's razor and Bayes' theorem

Occam’s razor says that if two models fit equally well, the simpler model is likely to be a better description of reality. Why should that be? A paper by Jim Berger suggests a Bayesian justification of Occam’s razor: simpler hypotheses

Tagged with: ,
Posted in Science, Statistics

Demand for simplicity?

From Donald Norman’s latest book Living with Complexity: … the so-called demand for simplicity is a myth whose time has passed, if it ever existed. Make it simple and people won’t buy. Given a choice, they will take the item

Tagged with:
Posted in Business

Some programmers really are 10x more productive

One of the most popular post on this site is Why programmers are not paid in proportion to their productivity. In that post I mention that it’s not uncommon to find some programmers who are ten times more productive than

Tagged with: ,
Posted in Uncategorized

Another math calendar from Ron Doerfler

Last year Ron Doerfler made a beautiful calendar with images from graphical computing, charts used as computational aids before desktop calculators were ubiquitous. Ron has made a new calendar and this year’s theme is lightning computing, tricks for mental calculation.

Tagged with:
Posted in Math

Weekend miscellany

Computing The wonderful world of early computing How to design programs Twitter Twitter accounts for all StackOverflow users by reputation and area One fact per day from computer science, math, statistics, etc. Science Elementary mechanics from a mathematician’s viewpoint Using

Posted in Uncategorized

Three views of differential equations

The most common view of differential equations may be sheer terror, but those who get past terror may have one of the following perspectives. Naive view: All differential equations can be solved in closed form by applying one of the

Tagged with: ,
Posted in Math

Obscenity

Classical Greek dramatists believed that it was degrading to show extreme emotion on stage. Some action had to be implied off stage (ob skene) because it was unfit to display explicitly. The classical idea of obscenity included sexual conduct, but

Posted in Uncategorized

Three P's and three I's of economics

In the December 27 episode of EconTalk, Pete Boettke summarizes basic economics as follows: If you don’t have the three P’s, you can’t have the three I’s. The three P’s are Property Prices Profit and loss The three I’s are

Tagged with:
Posted in Business

Style and understanding

From Let Over Lambda by Doug Hoyte: Style is necessary only when understanding is missing. A corollary to this is that sometimes the only way to effectively use something you don’t understand is to copy styles observed elsewhere. I liked

Tagged with: ,
Posted in Creativity, Software development

Top five non-technical posts of 2010

Most of last year’s most popular posts here were about math and programming. Here are the most popular posts from 2010 not about math or programming. (They may mention math or programming, but they’re not about math or programming.) Write-only

Posted in Uncategorized