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new2628

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That's an interesting response, thanks! I think where I disagree is that I think people are pretty smart, at least in one thing, which is survival -- the proof of that is that those who were not, quickly exited the gene pool. That is a powerful filtering that tunes our estimators.

I agree with your last paragraph, but I think it supports my point. I wear a mask because it has zero cost, and it may save my life. When I took this decision, I didn't estimate any probabilities and I haven't used Bayes theorem. Understanding what a mask does exactly and how aerosol transmission of viruses work precisely is almost irrelevant to my decision -- I could be improving my knowledge ("my priors") by studying virology, but there would still be so many uncertainties, that it would hardly influence my decision.

I agree with you, but my point is more broadly that in reality we often don't go through the steps "1. estimate probability" -> "2. make a decision based on the probability distribution", because step 1. is so error-prone and intractable, that we typically jump directly to step 2. and try to limit our downside.

Of course you could look back and say, given the fact that I took some decision, what would have been my prior if I had used Bayes theorem, but my point is that we don't actually use it for taking the decision.

There is always a prior only if you really care about computing probabilities. The implicit assumption in Bayesian data analysis is that you go first to "best possible estimate of probability", then to "decision based on that". My point was that you usually need not do the first step.

Example: I wear a bicycle helmet because it costs me next nothing and it possibly saves my life. I don't do any Bayesian analysis implicitly or explicitly, because on one side there is an outcome with value minus infinity, so it hardly matters what probability I multiply it with.

Controversial opinion: Bayes Theorem is overrated. In real life usually we have no idea about priors, and we have close to zero chance to get any good estimate of the true probability of something. But we can still get by fine for the most part, by focusing on limiting possible loss and staying on the safe side with large margins.

Many of the claimed cognitive biases go away under this view. One textbook example of Bayes theorem is how doctors overestimate the probability of being positive for a disease. But what are the priors? Maybe those who visit the doctor did something risky the day before or are feeling funny. Maybe the cost of false positive is negligible compared to the cost of a false negative, etc. People are less stupid than what the TED talk crowd claims.

Briar Project 6 years ago

This is like saying that the weapons advanced countries sell to less advanced countries are more "life-respecting".

That integrity of the West during and before the cold war included some nasty moves as well (Vietnam to name one). In fact, I find your thesis jingoism at its best.

I agree that in Berlin it is not as _major_ problem as in some other large cities, but still, it is telling that it is widely accepted as normal that all building corners that face the sidewalk are constantly pissed by dogs with the coloring of the walls clearly visible everywhere. As for poop, 90% of the times people pick it up, the rest can still ruin your day if you step into it.

Kissat SAT Solver 6 years ago

You can encode as moderately large (low hundreds of clauses/variables) SAT instances questions of Ramsey-theory and other unsolved combinatorics and those instances will not be solved by any heuristic.

Some of these skills (I would add: patience, focus, controlling anger, planning a few steps ahead) definitely transfer and are especially valuable to teach to children. But all these apply at the beginning already, for champion-level play the famous Morphy quote applies:

"The ability to play chess is the sign of a gentleman. The ability to play chess well is the sign of a wasted life."

A double twist is that in the original Hungarian his name is Élő that means "Live". For the first few decades of hearing "Élő"-score, I just assumed it meant your "live" score, as in your score at the current time. I wonder if others had that confusion too.

[dead] 6 years ago

At the risk of slight over-generalisation let me add:

No statue was ever about preserving history. It doesn't mean that there cannot be other good reasons for putting up statues.

At least in chess, if it is not the search, then it is probably the evaluation function.

Expert players have likely a very well-tuned evaluation function of how strong a board "feels". Some of it is explainable easily: center domination, diagonal bishop, connected pawn structure, rook supporting pawn from behind, others are more elaborate, come with experience and harder to verbalize.

When expert players play against computers, the limitation of their evaluation function becomes visible. Some board may feel strong, but you are missing some corner case that the minmax search observes and exploits.

This is quite common with many recent books: they are an extended essay. Most essays: an extension of one catchy phrase.