Author: Robert Hyatt
Date: 17:29:37 05/09/02
Go up one level in this thread
On May 09, 2002 at 18:08:52, J. Wesley Cleveland wrote: >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 I had this one covered already. King must have access to a2 in this position for it to kick in the 'drawn' scoring code... Otherwise it was too messy as the pawn and king are too close...
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.