Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Static Eval Test

Author: Robert Hyatt

Date: 05:36:38 09/08/02

Go up one level in this thread


On September 07, 2002 at 22:56:14, Peter McKenzie wrote:

>On September 07, 2002 at 22:40:06, Robert Hyatt wrote:
>
>>On September 07, 2002 at 19:46:49, Peter McKenzie wrote:
>>
>>>I've been having a break from computer chess post WCCC, but have now started
>>>going over some of Warp's games.  First up is Warp's worst game, the loss vs
>>>Brutus.  In this game, Warp showed a total lack of understanding of its
>>>centralised king in the early middlegame and lost without a fight.
>>>
>>>I present here the position after move 21 in the game.  White has grabbed a pawn
>>>thinking this position is OK, but in reality the white king is hopelessly stuck
>>>in the centre.  Also, white is passive, black is active and has a safe king,
>>>therefore white is totally winning here:
>>>
>>>[D]r1r3k1/1p3ppp/b5q1/p7/4n3/P3PNB1/1P3PPP/1Q1RK2R b K - 0 1
>>>
>>>I am curious what the static evaluation of various programs is here.  The
>>>version of warp used in Maastricht gives 0.238 in favour of white.  Ideally the
>>>static evaluation should favour black here I think.
>>>
>>
>>
>>Crafty says -.41 (good for black).  Here is output of "score" command:
>>
>>note: scores are for the white side
>>material evaluation.................   1.00
>>development.........................   0.00
>>pawn evaluation.....................   0.09
>>passed pawn evaluation..............   0.00
>>passed pawn race evaluation.........   0.00
>>king safety evaluation..............  -0.42
>>interactive piece evaluation........  -1.08
>
>that term seems to be the big one here, I guess it is mainly the B on a6
>preventing castling?
>
>cheers,
>Peter


It is actually king-safety related.  I have a function EvaluateKingSafety
that returns that -.42...  But that isn't the "whole story".  After doing
all the piece evaluations, there is another king safety term that is a
second/third-order type scoring term.  But it is inside Evaluate() which is
why it doesn't show up in king safety.  This -1.08 is a result of pieces
interacting together and a sense of "uneasiness" about the white king in the
center of the baord...

I'll try to get some details tonight...





>
>>total evaluation....................  -0.41
>>
>>
>>
>>
>>
>>>cheers,
>>>Peter



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.