Author: Uri Blass
Date: 03:52:52 05/21/01
This position could happen in kasparov-Deeper blue but kasparov did not play 40.gxh5 Based on Deeper blue logfiles we know that Deeper blue evaluated the position as 0.5 pawn advantage for white at depth 9(6)=15 Crafty's evaluation at depth 15 is 2.93 pawns for white so we can see that the difference in evaluation is 2.43 pawns. Part of the difference can be explained by different evaluation but most of the difference is clearly because of the fact that Crafty can see more than Deeper blue. Deeper blue found the line 40...Bxh5 41.Rh1 only at depth 10(6)=16 when Crafty could see it at depth 14 and the line was not changed at the next 2 plies. Crafty can see the line 40...Bxh5 41.Rh1 Bf3 42.Rg1 Bh5 43.g7 Nf3 44.Rg3 c5 45.bxc5 Rc8 46.f6 Rxc5 at depth 15 and 16 when Deeper blue can see it only at depth 17,18(deeper blue can see a different line but the difference is only 41...Kg5 42.Rg1 Kh6 that leads to the same position as 41..Bf3 42.Rg1 Bh5 and moves 43-46 are the same. It seems that Crafty is a very good program and it can outsearch deeper blue by 2 plies. I do not know the meaning of the plies of deeper blue but it seems to be not brute force search. I also doubt if deeper blue could search 200M nodes per second otherwise I cannot understand the reason that it is outsearched by other top programs again and again based on the pv's It is possible that the claims about 200M nodes per second were only a psychological war against kasparov Here is the analysis of Crafty kasparov - Deeper blue [D]3rr3/8/2p3Pk/1p2nP1P/pP2p3/P1B1Nb1B/2P2K2/5R2 b - - 0 1 Analysis by Crafty 18.08: 40...Kxh5 +- (1.42) Depth: 1/8 00:00:00 40...Kxh5 41.g7 Ng4+ 42.Bxg4+ Bxg4 +- (1.68) Depth: 2/8 00:00:00 40...Kg7 41.f6+ Kxf6 +- (1.53) Depth: 2/8 00:00:00 40...Kg7 41.f6+ Kxf6 42.Kg3 +- (1.53) Depth: 3/8 00:00:00 40...Kg7 41.Ng4 Bxg4 42.Bxg4 c5 +- (2.58) Depth: 4/10 00:00:00 40...Rd6 +- (2.18) Depth: 4/10 00:00:00 40...Rd6 41.Rg1 Bxh5 42.g7 Bf7 +- (2.03) Depth: 4/10 00:00:00 40...Kxh5 +- (1.63) Depth: 4/10 00:00:00 40...Bxh5 41.Bg2 Bf3 42.Bh3 ± (1.34) Depth: 4/10 00:00:00 40...Bxh5 41.Bg2 Nxg6 42.fxg6 Rf8+ 43.Ke1 Rxf1+ 44.Kxf1 Bxg6 ± (1.33) Depth: 5/16 00:00:00 40...Bxh5 41.Kg3 Kg5 42.Rf4 Bf3 43.Rh4 +- (1.62) Depth: 6/16 00:00:00 88kN 40...Bxh5 41.Rg1 Kg7 42.Bg4 Kh6 43.Bxe5 Rxe5 44.Rh1 +- (1.76) Depth: 7/19 00:00:01 222kN 40...Bxh5 41.Rg1 Nf3 42.Rh1 Kg5 43.g7 Rg8 44.f6 Kf4 +- (1.81) Depth: 8/20 00:00:01 480kN 40...Bxh5 41.Rg1 Nf3 42.Rh1 Ne5 43.Bg2 Nxg6 44.fxg6 Kxg6 +- (1.78) Depth: 9/23 00:00:03 1223kN 40...Kxh5 41.Rg1 Kh4 42.Bf1 Kh5 43.g7 Ng4+ 44.Nxg4 Bxg4 45.Rh1+ Kg5 46.f6 e3+ 47.Kg3 +- (1.77) Depth: 9/23 00:00:04 1778kN 40...Kxh5 41.Rg1 Kh4 42.Bg2 Bxg2 43.Rxg2 Kh5 44.g7 Nf7 45.Rg6 Nd6 46.Bd4 +- (2.01) Depth: 10/26 00:00:07 3318kN 40...Bxh5 41.Kg3 Kg5 42.g7 Nf7 43.f6 Rg8 44.Rf4 Bf3 45.Be6 Kg6 +- (1.94) Depth: 10/26 00:00:14 6548kN 40...Bxh5 41.Kg3 Kg5 42.g7 Nf7 43.f6 Rg8 44.Be6 Bg6 45.Rh1 Rd6 46.Bg4 +- (2.16) Depth: 11/27 00:00:24 11929kN 40...Kxh5 41.Rg1 Kh4 42.Bg2 Bxg2 43.Rxg2 Kh5 44.g7 Nf7 45.Bf6 Rd2+ 46.Kf1 Rxg2 47.Kxg2 +- (2.14) Depth: 11/27 00:00:33 16243kN 40...Kxh5 41.Rg1 Kh6 42.g7 Nf7 43.Rg6+ Kh7 44.Rxc6 Rc8 45.Rxc8 Rxc8 46.Bd4 Rd8 47.Bc3 Kg8 +- (2.53) Depth: 12/29 00:01:24 41952kN 40...Bxh5 41.Kg3 Kg5 42.g7 Nf3 +- (2.45) Depth: 12/29 00:01:48 54476kN 40...Bxh5 41.Kg3 Kg5 42.g7 Nf7 43.Rf4 Nd6 44.f6 Bg6 45.Rg4+ Kh5 46.Kf4 Rg8 47.Rg5+ Kh4 48.Be6 +- (2.71) Depth: 13/32 00:02:59 89583kN 40...Bxh5 41.Rh1 Kg5 42.Rg1+ Kf6 43.Bg2 Bf3 44.Bxf3 exf3 45.g7 Kf7 46.g8Q+ Rxg8 47.Rxg8 Rxg8 48.Bxe5 Re8 49.Ng4 +- (2.61) Depth: 14/34 00:08:56 267478kN 40...Bxh5 41.Rh1 Bf3 42.Rg1 Bh5 43.g7 Nf3 44.Rg3 c5 45.bxc5 Rc8 46.f6 Rxc5 47.Bb4 Rg5 48.Rxg5 Kxg5 +- (2.93) Depth: 15/39 00:23:36 722662kN 40...Bxh5 41.Rh1 Bf3 42.Rg1 Bh5 43.g7 Nf3 44.Rg3 c5 45.bxc5 Rc8 46.f6 Rxc5 47.Bb4 Rg5 48.Rxg5 Kxg5 49.Be7 +- (3.06) Depth: 16/40 00:43:40 1309529kN (Blass, Tel-Aviv 21.05.2001)
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