Mass_Driver:
I think this statement reflects either an ignorance of finance or the Dark Arts.
I'm not an expert on finance, but I am aware of everything you wrote about it in your comment. So I guess this leaves us with the second option. The Dark Arts hypothesis is probably that I'm using the extreme example of the stock market to suggest a general sweeping conclusion that in fact doesn't hold in less extreme cases.
To which I reply: yes, the stock market is an extreme example, but I honestly can't think of any other examples that would show otherwise. There are many examples of scientific models that provide more or less accurate probability estimates for all kinds of things, to be sure, but I have yet to hear about people achieving practical success in anything relevant by translating their common-sense feelings of confidence in various beliefs into numerical probabilities.
In my view, calibration of probability estimates can succeed only if (1) you come up with a valid scientific model which you can then use in a shut-up-and-calculate way instead of applying common sense (though you still need it to determine whether the model is applicable in the first place), or (2) you make an essentially identical judgment many times, and from your past performance you extrapolate how frequently the black box inside your head tends to be right.
Now, you try to provide some counterexamples:
I am (rationally) much more concerned about automobile accidents than fires, despite the fact that I know two people who have died in fires and none who have died in automobile accidents. I know this based on my inferences from published statistics, the reliability of which I make further inferences about. I am quite confident (p ~ .95) that it is sensible to drive defensively (at great cost in effort and time) while essentially ignoring fire safety (even though checking a fire extinguisher or smoke detector might take minimal effort.)
Frankly, the only subjective probability estimate I see here is the p~0.95 for your belief about driving. In this case, I'm not getting any more information from this number than if you just described your level of certainty in words, nor do I see any practical application to which you can put this number. I have no objection to your other conclusions, but I see nothing among them that would be controversial to even the most extreme frequentist.
Not sure who voted down your reply; it looks polite and well-reasoned to me.
I believe you when you say that the stock market was honestly intended as representative, although, of course, I continue to disagree about whether it actually is representative.
Here are some more counterexamples:
*When deciding whether to invest in an online bank that pays 1% interest or a local community bank that pays 0.1% interest, I must calculate the odds that each bank will fail before I take my money out; I cannot possibly have a scientific model that generates replicable re...
Please read the post before voting on the comments, as this is a game where voting works differently.
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Here's an irrationalist game meant to quickly collect a pool of controversial ideas for people to debate and assess. It kinda relies on people being honest and not being nitpickers, but it might be fun.
Write a comment reply to this post describing a belief you think has a reasonable chance of being true relative to the the beliefs of other Less Wrong folk. Jot down a proposition and a rough probability estimate or qualitative description, like 'fairly confident'.
Example (not my true belief): "The U.S. government was directly responsible for financing the September 11th terrorist attacks. Very confident. (~95%)."
If you post a belief, you have to vote on the beliefs of all other comments. Voting works like this: if you basically agree with the comment, vote the comment down. If you basically disagree with the comment, vote the comment up. What 'basically' means here is intuitive; instead of using a precise mathy scoring system, just make a guess. In my view, if their stated probability is 99.9% and your degree of belief is 90%, that merits an upvote: it's a pretty big difference of opinion. If they're at 99.9% and you're at 99.5%, it could go either way. If you're genuinely unsure whether or not you basically agree with them, you can pass on voting (but try not to). Vote up if you think they are either overconfident or underconfident in their belief: any disagreement is valid disagreement.
That's the spirit of the game, but some more qualifications and rules follow.
If the proposition in a comment isn't incredibly precise, use your best interpretation. If you really have to pick nits for whatever reason, say so in a comment reply.
The more upvotes you get, the more irrational Less Wrong perceives your belief to be. Which means that if you have a large amount of Less Wrong karma and can still get lots of upvotes on your crazy beliefs then you will get lots of smart people to take your weird ideas a little more seriously.
Some poor soul is going to come along and post "I believe in God". Don't pick nits and say "Well in a a Tegmark multiverse there is definitely a universe exactly like ours where some sort of god rules over us..." and downvote it. That's cheating. You better upvote the guy. For just this post, get over your desire to upvote rationality. For this game, we reward perceived irrationality.
Try to be precise in your propositions. Saying "I believe in God. 99% sure." isn't informative because we don't quite know which God you're talking about. A deist god? The Christian God? Jewish?
Y'all know this already, but just a reminder: preferences ain't beliefs. Downvote preferences disguised as beliefs. Beliefs that include the word "should" are are almost always imprecise: avoid them.
Additional rules: