Technical Explanation (of Bayes' theorem)

yudkowsky.net

56 points·olalonde··5 comments

See also the intuitive explanation:

Hilarious blurb about priors about 1/3rd of the way in.

Q. How can I find the priors for a problem? A. Many commonly used priors are listed in the Handbook of Chemistry and Physics.

Q. Where do priors originally come from? A. Never ask that question.

Q. Uh huh. Then where do scientists get their priors? A. Priors for scientific problems are established by annual vote of the AAAS. In recent years the vote has become fractious and controversial, with widespread acrimony, factional polarization, and several outright assassinations. This may be a front for infighting within the Bayes Council, or it may be that the disputants have too much spare time. No one is really sure.

Q. I see. And where does everyone else get their priors? A. They download their priors from Kazaa.

Q. What if the priors I want aren't available on Kazaa? A. There's a small, cluttered antique shop in a back alley of San Francisco's Chinatown. Don't ask about the bronze rat.

I find this to be an even better explanation: http://oscarbonilla.com/2009/05/visualizing-bayes-theorem/

I like that one too. Yudkowsky's article is way too long for the casual reader.

I respect HN people who could made it to even half of this.

The theorem itself is fairly trivial, the article's goal is helping to build intuitions guided by the theorem. That's why it is so long.

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