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Subject: Re: The probability to find better move is simply irrelevant for diminishing

Author: Uri Blass

Date: 12:52:50 02/09/02

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On February 09, 2002 at 14:54:07, Sune Fischer wrote:

>On February 09, 2002 at 14:12:18, Uri Blass wrote:
>
>>On February 09, 2002 at 11:37:41, Sune Fischer wrote:
>>
>>>On February 09, 2002 at 11:14:05, Uri Blass wrote:
>>>
>>>>On February 09, 2002 at 07:44:27, Sune Fischer wrote:
>>>>
>>>>>On February 09, 2002 at 07:08:35, Uri Blass wrote:
>>>>>
>>>>>>returns.
>>>>>>
>>>>>>Imagine the following simple game:
>>>>>>Every side need to say in it's turn if it resigns or not resign.
>>>>>>The game is finished only when one side resigns.
>>>>>>
>>>>>>If both sides never resign the game is never finished.
>>>>>>
>>>>>>
>>>>>>Imagine the following 3 programs for that simple game:
>>>>>>
>>>>>>
>>>>>>Program A resigns with probability of 10% in every move
>>>>>>Program B resigns with probability of 1% in every move
>>>>>>Program C never resigns.
>>>>>>
>>>>>>program C finds better move than program B only in 1% of the cases but in games
>>>>>>C always wins against B(B will do a mistake of resigning after enough moves).
>>>>>
>>>>>No, this is where you get it wrong IMO.
>>>>>See C will not _always_ beat B, because the games will end at some point and
>>>>>this will give B a winning probability greater than zero.
>>>>
>>>>Not in the game that I described.
>>>>
>>>>I agree that at some point there is diminshing returns in chess and I believe
>>>>that it happens a lot before chess is solved but the point is that using
>>>>statistics about the probability to change your mind is a wrong way to get a
>>>>conclusion.
>>>
>>>Well you mentioned 1%, not me:)
>>>Chess _is_ statistics, the weaker side always has a chance, a 2400 player can
>>>beat a 2700 player once and a while (why else even play the match?).
>>>
>>>Maybe I misunderstood your game, in your game it seems B will resign even in a
>>>completely drawn positions such as K-BK because, C will never stop playing the
>>>game so B might resign before the 50 move rule. That is a strange game I think.
>>>
>>>-S.
>>
>>In my game there is no 50 move rule and it is not chess.
>>
>>The point is that even if the probability to change your mind is smaller you
>>cannot learn from it that the rating difference is smaller.
>>
>>I cannot give a correct model of what happens in chess so I try to look at a
>>simpler game.
>>
>>I can  also look at chess and look at a simple strategy assuming that you know
>>the right moves.
>>
>>imagine that chess is a draw and
>>imagine the following players in chess:
>>
>>player A:always plays the correct move
>>
>>player B: always plays the correct move after move 60 when in the first 60 moves
>>plays the correct move in 95% of the cases and resigns in the rest of the cases.
>>
>>player C:the same as B when 89% is used instead of 95%
>>
>>It is clear that if you do a match between A and B you will get higer result
>>than the case that you do a match between B and C inspite of the fact that you
>>can say that B is 6% better than C when A is only 5% is better than B.
>>
>>Uri
>
>I think something is wrong with your example.
>Since all games can last infinite, it means A can drag the game on forever and
>just wait for the opponent to make a mistake, so A _always_ wins.
>I don't know the rating formula, but it seems to me A must have an infinite
>rating since it will never even draw.
>This is a complete breakdown, A is beyond Godness, even God would not have an
>infinite chess rating, so something needs to be fixed.
>
>The game must end, in fact this is probably a non-trivial rule about chess.
>
>-S.

In the last example the game ends and if no player resigned before move 60 it is
a draw.

Uri



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