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Comment by evec on Against utility functions · 2014-06-22T21:03:03.932Z · LW · GW

Sure. Say you have to make some decision now, and you will be asked to make a decision later about something else. Your decision later may depend on your decision now as well as part of the world that you don't control, and you may learn new information from the world in the meantime. Then the usual way of rolling all of that up into a single decision now is that you make your current decision as well as a decision about how you would act in the future for all possible changes in the world and possible information gained.

This is vaguely analogous to how you can curry a function of multiple arguments. Taking one argument X and returning (a function of one argument Y that returns Z) is equivalent to taking two arguments X and Y and returning X.

There's potentially a huge computational complexity blowup here, which is why I stressed mathematical equivalence in my posts.

Comment by evec on Against utility functions · 2014-06-20T22:16:24.909Z · LW · GW

Let me rephrase: would you like to describe your arguments against utility functions in more detail?

For example, as I mentioned, there's an obvious mathematical equivalence between making a plan at the beginning of time and planning as you go, which is directly analogous to how one converts games from extensive-form to normal-form. As such, all aspects of acquiring information is handled just fine (from a mathematical standpoint) in the setup of vNM.

The standard response to the discussion of knowing probabilities exactly and to concerns about computational complexity (in essence) is that we may want to throw aside epistemic concerns and simply learn what we can from a theory that is not troubled by them (a la air resistance in physics..)? Is your objection essentially that those factors are more dominant in human morality than LW acknowledges? And if so, is the objection to the normal-form assumption essentially the same?

Comment by evec on Against utility functions · 2014-06-19T21:29:05.037Z · LW · GW

I think your original post would have been better if it included any arguments against utility functions, such as those you mention under "e.g." here.

Besides being a more meaningful post, we would also be able to discuss your comments. For example, without more detail, I can't tell whether your last comment is addressed sufficiently by the standard equivalence of normal-form and extensive-form games.

Comment by evec on Does Checkers have simpler rules than Go? · 2013-08-15T22:21:50.819Z · LW · GW

I don't believe your comment is true in any meaningful sense. Can you explain what you mean?

Details: It's easy to prove that the first player wins in Hex without the swap rule, but it's even easier to prove the second wins in any (deterministic, ...) game with the swap rule. Neither proof is constructive, and so neither provides an efficient program.

Interpreting your statement differently, it's easy to write a program that plays any (deterministic, ...) game optimally. Just explore the full game tree! The program won't terminate for a while, however, and this interpretation makes no distinction between the versions with and without the swap rule.

Comment by evec on Prisoner's dilemma tournament results · 2013-07-10T23:19:50.121Z · LW · GW

Why does submitting CooperateBot to a competition that does not include it make someone a troll? Would submitting DefectBot make one a troll, too?

(I believe the competition should have automatically included one CooperateBot and DefectBot each, and stated that this was the case at the beginning. I am sad there were three CooperateBots and no DefectBots.)

Comment by evec on What bothers you about Less Wrong? · 2011-05-24T02:21:59.713Z · LW · GW

Does checking http://lesswrong.com/r/all/new solve the problem of checking two places?