Bayes’ Theorem – What is it and what is it good for? • Hacker News Board

Re: Bayes’ Theorem – What is it and what is it good for?

#31

Post by darkxanthos » Fri, Jun 26, 2015, 3:54 PM UTC

dimino wrote: post #29

darkxanthos wrote: post #24

Earlier quoted context omitted.

Two points: 1. Bayesian statistics allows use of "uninformative" priors. 2. Discarding your subjective beliefs is less than ideal as well as overweighting them. You have beliefs due to your experience. Weight them lightly but still use them. In the absence of much information your calculations will follow your gut. What else do you have in the absence of other information ? Using quantified subjective beliefs at leas…

I don't think it's as rigorously defined as it's purported to be. I just envision the practical application of manipulating values to produce desired results, and then post-hoc rationalizing those value manipulations to obtain a higer-than-warranted level of confidence in the result, because, "I applied rigor!"

The math is well defined and rigorous not every analysis that uses it. I think you're conflating those two things.

Re: Bayes’ Theorem – What is it and what is it good for?

#32

Post by darkxanthos » Fri, Jun 26, 2015, 3:57 PM UTC

jhallenworld wrote: post #15

I recently started to think about connections between Bayes' Theorem and fuzzy logic: http://sipi.usc.edu/~kosko/Fuzziness_Vs_Probability.pdf (also from wikipedia on fuzzy logic): "Bruno de Finetti argues[citation needed] that only one kind of mathematical uncertainty, probability, is needed, and thus fuzzy logic is unnecessary. However, Bart Kosko shows in Fuzziness vs. Probability that probability theory is a subth…

Thank you for sharing this! It stretched my mind a bit. :)

Re: Bayes’ Theorem – What is it and what is it good for?

#33

Post by davidgerard » Fri, Jun 26, 2015, 4:21 PM UTC

darkxanthos wrote: post #31

dimino wrote: post #29

Earlier quoted context omitted.

I don't think it's as rigorously defined as it's purported to be. I just envision the practical application of manipulating values to produce desired results, and then post-hoc rationalizing those value manipulations to obtain a higer-than-warranted level of confidence in the result, because, "I applied rigor!"

The math is well defined and rigorous not every analysis that uses it. I think you're conflating those two things.

He's talking about the practical effects of fallible humans using the version of Bayes advocated in the original post (citing Yudkowsky and Muehlhauser).

Pulling numbers out of your backside and running them through a process makes you more confident than just pulling them out of your backside directly, but I've yet to see evidence it does more than increasing your confidence.

Re: Bayes’ Theorem – What is it and what is it good for?

#34

Post by dimino » Fri, Jun 26, 2015, 5:07 PM UTC

darkxanthos wrote: post #31

dimino wrote: post #29

Earlier quoted context omitted.

I don't think it's as rigorously defined as it's purported to be. I just envision the practical application of manipulating values to produce desired results, and then post-hoc rationalizing those value manipulations to obtain a higer-than-warranted level of confidence in the result, because, "I applied rigor!"

The math is well defined and rigorous not every analysis that uses it. I think you're conflating those two things.

Oh yes, I wouldn't question the math -- it's well beyond my expertise, and I've heard of way too many implementations of the theory to refute it at a theoretical level.

Re: Bayes’ Theorem – What is it and what is it good for?

#35

Post by davidgerard » Fri, Jun 26, 2015, 7:20 PM UTC

DennisP wrote: post #23

> the Standard Model of particle physics explains much, much more than thunderstorms, and its rules could be written down in a few pages of programming code. As a programmer who doesn't know advanced math, I'd really like to see that code, in literate form.

This is a Yudkowskyism, i.e. don't expect to see the code, or if you do then expect it to have obvious defects.