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Subject: Re: initial position again...

Author: Ricardo Gibert

Date: 03:11:17 09/10/00

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On September 09, 2000 at 15:19:58, José de Jesús García Ruvalcaba wrote:

>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.

When I said:

"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."

This was incorrect. I retract that now, but I see nothing wrong with the rest.

>
>>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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