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Subject: Re: Can your program see the draw ? More info (again)

Author: J. Wesley Cleveland

Date: 15:08:52 05/09/02

Go up one level in this thread


On May 09, 2002 at 13:22:01, Robert Hyatt wrote:

>On May 09, 2002 at 12:43:08, Robert Hyatt wrote:
>
>>On May 08, 2002 at 16:22:16, J. Wesley Cleveland wrote:
>>
>>>In this position which is an obvious draw for any decent human player,
>>>[D]8/8/p2b4/8/p7/3k4/1B6/1K6 w - - 0 4
>>>crafty is clueless - static evaluation is -3.19, evaluation after 34 ply is
>>>still -3.19.
>>
>>
>>This is a harder case that my current "knowledge" doesn't cover.  Black
>>has the right bishop for its rook pawns.  Of course white has the same
>>colored bishop and if they are traded, it is a draw because of simple
>>rook pawns left with the opposing king controlling the queening square.
>>
>>I can fix this cheaply and will.  But it is simply a good illustration of
>>just how many special cases there are in endgames that computers have to
>>handle...
>>
>>Be interesting to see if any program currently has this evaluation knowledge
>>to call this a draw, statically.  It is doable.
>
>
>Old version:
>
>material evaluation.................  -2.00
>development.........................   0.00
>pawn evaluation.....................  -0.24
>passed pawn evaluation..............   0.00
>passed pawn race evaluation.........   0.00
>king safety evaluation..............   0.00
>interactive piece evaluation........  -0.92
>total evaluation....................  -3.16
>
>
>new version:
>
>material evaluation.................  -2.00
>development.........................   0.00
>pawn evaluation.....................  -0.24
>passed pawn evaluation..............   0.00
>passed pawn race evaluation.........   0.00
>king safety evaluation..............   0.00
>interactive piece evaluation........   2.24
>total evaluation....................   0.00
>
>Fix was straightforward to do without hurting performance...  Just had to
>"explain" to it that the right bishop is no good if the opponent has one
>too...

You need to be carefule here - this position is won for black.
[D]8/8/p2b1B2/8/8/pk6/8/1K6 w - - 0 1




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