Monthly Archives: September 2011

Just an approximation

I find it amusing when I hear someone say something is “just an approximation” because their “exact” answer is invariably “just an approximation” from someone else’s perspective. When someone says “mere approximation” they often mean “that’s not the kind of

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Posted in Math

C programs and reading rooms

This evening I ran across Laurence Tratt’s article How can C Programs be so Reliable? Tratt argues that one reason is that C’s lack of a safety net makes developers more careful. Because software written in C can fail in

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Posted in Software development

A Bayesian view of Amazon Resellers

I was buying a used book through Amazon this evening. Three resellers offered the book at essentially the same price. Here were their ratings: 94% positive out of 85,193 reviews 98% positive out of 20,785 reviews 99% positive out of

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Posted in Statistics

Sed one-liners

A few weeks ago I reviewed Peteris Krumins’ book Awk One-Liners Explained. This post looks at his sequel, Sed One-Liners Explained. The format of both books is the same: one-line scripts followed by detailed commentary. However, the sed book takes

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Posted in Software development

California knows cancer

Last week I stayed in a hotel where I noticed this sign: This building contains chemicals, including tobacco smoke, known to the State of California to cause cancer, birth defects, or other reproductive harm. I saw similar signs elsewhere during

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Posted in Science

The difference between science fiction and fantasy

“The difference between science fiction and fantasy … is simply this: science fiction has rivets and fantasy has trees.” — Orson Scott Card

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New tech reports

Soft maximum I had a request to turn my blog posts on the soft maximum into a tech report, so here it is: Basic properties of the soft maximum There’s no new content here, just a little editing and more

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Posted in Math

Professional volunteers

This afternoon I saw a fire truck with the following written on the side: Staffed by professional volunteers Of course this is an oxymoron if you take the words literally. A more accurate slogan would be Staffed by well-qualified amateurs

Posted in Business

Big data and humility

One of the challenges with big data is to properly estimate your uncertainty. Often “big data” means a huge amount of data that isn’t exactly what you want. As an example, suppose you have data on how a drug acts

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Posted in Science, Statistics, Uncategorized

Thomas Hardy and Harry Potter

Emily Willingham mentioned on Twitter that the names of the Harry Potter characters Dumbledore and Hagrid come from Thomas Hardy’s 1886 novel The Mayor of Casterbridge. Both appear in this passage: One grievous failing of Elizabeth’s was her occasional pretty

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Two suns in the sunset

NASA’s Kepler mission has discovered a planet orbiting two stars, something like Tatooine in Star Wars. However, unlike Tatooine, this planet is a gas giant about the size and mass of Saturn. But if you had a place to stand

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Tuesday miscellany

Health Why is health care so expensive? An immune system trained to kill cancer Linguistics Why some languages sound so fast Software development Keyboard heat maps for different languages WinRT demystified WinRT and .NET Math Magic square with a twist

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Latitude doesn’t exactly mean what I thought

Don Fredkin left a comment on my previous blog post that surprised me. I found out that latitude doesn’t exactly mean what I thought. Imagine a line connecting your location with the center of the Earth. I thought that your

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Journey away from the center of the Earth

What point on Earth is farthest from its center? Mt. Everest comes to mind, but its summit is the point highest above sea level, not the point farthest from the center. These are not the same because the Earth is

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Compound complexity

I’ve started to read through Michael Fogus’ list of recommended technical papers and ran across this gem from Out of the Tar Pit: Complexity breeds complexity. There are a whole set of secondary causes of complexity. This covers all complexity

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Posted in Software development