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Subject: Re: initial position again...

Author: José de Jesús García Ruvalcaba

Date: 12:19:58 09/09/00

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On September 09, 2000 at 12:33:08, Ricardo Gibert wrote:

>On September 09, 2000 at 08:44:57, Antonio Dieguez wrote:
>
>>On September 09, 2000 at 02:13:19, Ricardo Gibert wrote:
>>
>>>On September 08, 2000 at 19:05:20, Antonio Dieguez wrote:
>>>
>>>>just for fun, can you do a search with your program in the initial position?
>>>>
>>>>rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
>>>>
>>>>here is for amyan, unrealistic evals? 1/3 of a pawn just for one piece more
>>>>developed hum... may be better something a bit exponential?
>>>>
>>>>[2] -0.01      87  e2e4 e7e5
>>>>[3] +0.35     426  e2e4 g8f6 b1c3
>>>>[4] -0.01    2021  d2d4 d7d5 g1f3 g8f6
>>>>[5] +0.32    7746  e2e4 e7e5 g1f3 g8f6 b1c3
>>>>[6] +0.12   24010  e2e4 e7e5 g1f3 g8f6 f1c4 b8c6
>>>>[7] +0.30   63896  e2e4 e7e5 g1f3 g8f6 b1c3 b8c6 d2d4 e5d4 f3d4
>>>>[8] +0.16  282830  e2e4 e7e5 g1f3 g8f6 f1c4 f6e4 d2d3 e4d6 f3e5
>>>>[9] +0.27 1086340  e2e4 e7e6 b1c3 g8f6 g1e2 f8b4 e4e5 f6d5 d2d4
>>>>
>>>>just me.
>>
>>hello
>>
>>>Theoretically it should be about 1/6th of a pawn. If White is 1/3rd of a pawn
>>>better than "even", then Black is 1/3rd of a pawn worse than "even" or in other
>>>words, White is 2/3rds of a pawn better than Black, which can't be right.
>>
>>no, +1/3 for white means white is 1/3 of a pawn better than black.
>
>Are you sure? Lets say I am White. We are in the beginning position. I have the
>advantage, since it is my turn to move. Now if I drop a tempo, then it is now
>you who are effectively playing White and now you have the advantage.
>
>This different from the situation of my being a pawn up. Now If I drop a clear
>pawn, you do not assume the advantage of being a pawn up. The material is now
>equal. I would have to drop 2 pawns for the roles to be reversed. Do you see how
>it is different?
>

Hi Ricardo,
	your reasoning is wrong! But since you are a very smart guy fully capable of
finding out why, I will not spoil it for you.
José.

>Now consider what happens when White wins a clear pawn. His advantage of the
>move does not disappear, he then has the pawn PLUS the advantage of being White.
>If he were only exactly a pawn up, White would have to drop a ½ tempo. Do you
>now see why some say a pawn is worth about 2½ tempos? I think it is worth about
>3, but I can see why there is the alternative interpretation.
>
>>very ugly speak this way about chess anyway :)
>>
>>>With White being 1/6th of a pawn better than "even", then Black is 1/6th of a
>>>pawn worse than even, so now White is now 1/3rd of a pawn better than Black,
>>>which is what you would expect. I remember some guy on ICC reported .17 with one
>>>of the commercial programs, which is consistent with 1/6th of a pawn.
>>
>>.17 doens't seem rare, i will implement an exponential function for development
>>and also for king danger patterns. May be the average between x and x^2, or
>>something like that.
>>
>>>With the eval oscillating with odd or even depth, you should be getting a ½
>>>tempo better on odd ply and zero on even ply. You're showing instead about 1
>>>tempo better on even ply and about a ½ tempo better on odd ply.
>>
>>hey, in the initial position white plays and wins!
>>ok I get it but is not so simple.
>>
>>>All this assumes a pawn is worth 3 tempos, but some would say it is worth only
>>>2½ pawns. Take your pick.
>>
>>mmmh...



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