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Open Thread Winter 2024/2025
roland6mo*10

I'm looking for something simpler that doesn't require understanding another concept besides probability.

The article you posted is a bit confusing:

the likelihood of X given Y is just the probability of Y given X!

help us remember that likelihoods can't be converted to probabilities without combining them with a prior.

So is :

In this case, the "Miss Scarlett" hypothesis assigns a likelihood of 20% to e

Fixed: the "Miss Scarlett" hypothesis assigns a probability of 20% to e

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Open Thread Winter 2024/2025
roland6mo*50

Update: Confusion of the Inverse

Is there an aphorism regarding the mistake P(E|H) = P(H|E) ?

Suggestions:

  1. Thou shalt not reverse thy probabilities!
  2. Thou shalt not mix up thy probabilities!
  3. Thou shalt not invert thy probabilities! -- Based on Confusion of the Inverse

Example 2

Suppose you're Sherlock Holmes investigating a case in which a red hair was left at the scene of the crime.

The Scotland Yard detective says, "Aha! Then it's Miss Scarlet. She has red hair, so if she was the murderer she almost certainly would have left a red hair there. P(redhair∣Scarlet)=99%, let's say, which is a near-certain conviction, so we're done."

"But no," replies Sherlock Holmes. "You see, but you do not correctly track the meaning of the conditional probabilities, detective. The knowledge we require for a conviction is not P(redhair∣Scarlet), the chance that Miss Scarlet would leave a red hair, but rather P(Scarlet∣redhair), the chance that this red hair was left by Scarlet. There are other people in this city who have red hair."

"So you're saying..." the detective said slowly, "that P(redhair∣Scarlet) is actually much lower than 1?"

"No, detective. I am saying that just because P(redhair∣Scarlet) is high does not imply that P(Scarlet∣redhair) is high. It is the latter probability in which we are interested - the degree to which, knowing that a red hair was left at the scene, we infer that Miss Scarlet was the murderer. This is not the same quantity as the degree to which, assuming Miss Scarlet was the murderer, we would guess that she might leave a red hair."

"But surely," said the detective, "these two probabilities cannot be entirely unrelated?"

"Ah, well, for that, you must read up on ."

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Open Thread Fall 2024
roland8mo10

Bayes for arguments: how do you quantify P(E|H) when E is an argument? E.g. I present you a strong argument supporting Hypothesis H, how can you put a number on that?

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My Number 1 Epistemology Book Recommendation: Inventing Temperature
roland9mo10

His other books are also great.

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Critical review of Christiano's disagreements with Yudkowsky
roland2y10

that it’s reasonably for Eliezer to not think that marginally writing more will drastically change things from his perspective.

Scientific breakthroughs live on the margins, so if he has guesses on how to achieve alignment sharing them could make a huge difference.

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Critical review of Christiano's disagreements with Yudkowsky
roland2y*21

I have guesses

Even a small probability of solving alignment should have big expected utility modulo exfohazard. So why not share your guesses?

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Updates and Reflections on Optimal Exercise after Nearly a Decade
roland2y10

Weighted step ups instead of squats

Lunges vs weighted step ups?

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Updates and Reflections on Optimal Exercise after Nearly a Decade
roland2y10

Source please

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Updates and Reflections on Optimal Exercise after Nearly a Decade
roland2y10

why would a weighted step up be better and safer than a squat?

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Bayes' rule
Arbital conditional probability
Arbital
17Open & Welcome Thread—May 2020
5y
50
4roland's Shortform
5y
1
12Welcome and Open Thread June 2019
6y
35
-8The sad state of Rationality Zürich - Effective Altruism Zürich included
7y
50
0Intuitive explanation of why entropy maximizes in a uniform distribution?
8y
7
-5Good forum for investing?
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23Cryonics in Europe?
11y
2
5Life insurance for Cryonics, how many years?
11y
12
2Meetup Zürich last minute
11y
0
2Meetup : Zurich/Zürich meetup (come out of the woodwork)
11y
0
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