Author: Uri Blass
Date: 04:46:58 12/06/04
Go up one level in this thread
On December 06, 2004 at 07:01:26, Uri Blass wrote: >On December 06, 2004 at 06:59:58, Uri Blass wrote: > >>On December 06, 2004 at 06:52:33, Uri Blass wrote: >> >>>On December 06, 2004 at 00:33:31, Anthony Cozzie wrote: >>> >>>>Every so often when Zappa and Crafty play, they come up with some really >>>>brilliant moves and tough positions. Somehow, when I watched this game I had an >>>>intense image of two boxers who just refused to give up, no matter how bloodied >>>>they were. You can judge for yourself. The opening was a French defense, with >>>>Zappa defending. Zappa had a few tense moments, but it was able to get a very >>>>solid position, despite the horrible French bishop. Zappa thought it was about >>>>equal, while Crafty liked white to the tune of about +0.6. I guess the true >>>>value is somewhere in between; Black should draw but I think White has all the >>>>winning chances here. >>>> >>>>[D]2r1r1k1/3bq2p/p5pQ/Pp1pPp2/3P4/3B1R2/2P3PP/5RK1 b - - 0 24 >>>> >>>>So they shuffled, as computers are wont to do, and Crafty was finally so happy >>>>with its position that it gave away the a5 pawn in order to prevent the draw. >>>>At this point Crafty was about +0.4, while Zappa thought it was winning by 0.7 >>>>or so. The shuffling continued, with Zappa trying to advance its passed a pawn >>>>without letting Crafty checkmate it on the kingside. >>>> >>>>[D]2r4k/7p/p3b1p1/qp1pPp2/3P1R2/2rB2R1/2P3PP/4Q1K1 w - - 0 38 >>>> >>>>Here came the first problem. Zappa had counted on Kg8, but white has a draw in >>>>that line. >>>> >>>>[D]2r5/6kp/4b1p1/1p1pPp2/pq1P3Q/2rB2R1/2P3PP/5RK1 b - - 0 45; bm Qf8; test >>>>position 1 >>>> >>>>1... Kg7-g8 2. Rg3-h3 Rc3-c7 3. c2-c3 Qb4xc3 4. Bd3xb5 Qc3-b4 5. Bb5-a6 Rc8-b8 >>>>6. Rf1-e1 a4-a3 >>>> = (1.13) Depth: 11/33 00:00:08.83 4885kN (553 KN/s, 0 splits, 0 aborts) >>>>1... Kg7-g8 2. Qh4-f6 Rc3-c6 3. Rg3xg6 h7xg6 4. Qf6xg6 Kg8-h8 5. Qg6-h6 Kh8-g8 >>>>6. Qh6-g6 >>>> = (0.00) Depth: 12/33 00:00:12.63 7287kN (577 KN/s, 0 splits, 0 aborts) >>>>1... Qb4-f8 2. Rg3-h3 h7-h5 3. Rh3-g3 Kg7-h7 4. Bd3xb5 Rc3xg3 5. Qh4xg3 Qf8-b4 >>>>6. Qg3-d3 a4-a3 7. Rf1-f3 >>>> = (0.56) Depth: 12/34 00:00:28.62 17188kN (600 KN/s, 0 splits, 0 aborts) >>>> >>>>This let Crafty win the b5 pawn, and the shuffling continued. Zappa was able to >>>>get its a pawn to a2, but it remained hampered by its horrible bishop. Finally, >>>>just when Crafty thought it had equalized, Zappa struck: >>>> >>>>[D]8/r5k1/4b1p1/1q1pPp1p/3P4/2P3P1/p4K1P/R1QB4 b - - 0 68; bm f4! test position >>>>2 >>>> >>>>1... f5-f4 2. g3xf4 Be6-f5 3. Bd1-c2 Bf5-g4 4. Kf2-g1 Qb5-e2 5. Bc2-b3 Bg4-e6 6. >>>>f4-f5 g6xf5 7. Qc1-g5 Kg7-h7 >>>> = (1.14) Depth: 13/36 00:00:38.98 29001kN (744 KN/s, 0 splits, 0 aborts) >>>> >>>>After some complicated tactics, Zappa emerged with a Rook versus Crafty's 3 >>>>passed pawns. When I was just about to celebrate a pretty win, Zappa threw the >>>>game away with Rf4??. This is a really hard position for Zappa, because after >>>>Rf4 d5 it has a Rook and Bishop vs 2 connected passers, whereas after Bf5 it has >>>>a Rook vs 3 connected passers :) Crafty gets it at 8 ply or so though. >>>> >>>>[D]8/7k/4Prp1/7p/2BP4/2P5/7P/1b4K1 b - - 0 82; bm Bf5!; test position 3 >>>> >>>>After Rf4 Crafty was able to force the draw, although Zappa didn't realize it >>>>for another 10 moves. The final position: >>> >>> >>>Not a good test position. >>> >>>It is possible to find Bf5 for the wrong reason. >>>Movei also needs 8 plies to find it but needs depth 13 to find Crafty's d5(still >>>without a draw score). >>> >>>Note also that I expect zappa to find Bf5 after more time simply because it wins >>>material and from computer point of view it should not be. >>> >>>Movei after some time has fail high on Bf5 >>> >>>I am also not sure if d5 force a draw and movei does not agree with capturing >>>the bishop after d5 and suggests the line d5 Bf5 d6 Re4 >>> >>>At this moment of posting I see another fail high for d5 so maybe not capturing >>>the bishop also does not help. >>>I am surprised that zappa fail here relative to movei because I expect movei to >>>be weak in endgame considering the fact that it does not use hash for pruning. >>> >>>Uri >> >>It seems that the fail high was a wrong fail high. >> >>I also checked the position after Rxc4 and I find that movei can see a draw >>score after a minute of search and even has a positive score of +0.08 for white >>at depth 14. >> >>Maybe Crafty even missed a win but I will need more reliable program like yace >>to check it. >> >>Note that the version of movei that I used of movei is the public version and >>the cahnges that I did from it until now are only cosmetic changes like allowing >>more personalities and no change in the evaluation. >> >>Uri > >I see after posting that the score at depth 15 is again negative score for >white. > >Uri It seems that 83...Rxc4 is the drawing error of zappa. Analyzing with yace when I go backward show 0.00 score after 83...Rxc4 Instead of 83...Rxc4 it likes Bf5 like movei and the score seems to go up every iteration from depth 15 to depth 18 Crafty-19.14 - Zappa, Computer chess game 2004 8/7k/4P1p1/3P3p/2B2r2/2P5/7P/1b4K1 b - - 0 1 Analysis by Yace 0.99.87: 83...Rxc4 84.d6 Rg4+ 85.Kf2 Rh4 86.d7 Rxh2+ 87.Ke1 Rh1+ 88.Ke2 Rh2+ 89.Ke1 Rh1+ 90.Ke2 Rh2+ 91.Ke1 = (0.00) Depth: 1 00:00:00 µ (-1.37) Depth: 15/41 00:00:55 93231kN 83...Bf5 84.d6 Re4 85.d7 Re1+ 86.Kf2 Rd1 87.Bb3 Rd6 88.h4 Kg7 89.c4 Kf6 90.c5 Rd2+ 91.Ke3 Rd3+ 92.Ke2 Ke7 µ (-1.37) Depth: 15/41 00:01:38 162313kN 83...Bf5 84.d6 Re4 85.d7 Re1+ 86.Kf2 Rd1 87.Bb3 Rd6 88.e7 Bxd7 89.Ba4 Bxa4 90.e8R -+ (-1.77) Depth: 16/41 00:01:54 187651kN 83...Bf5 84.d6 Re4 85.d7 Re1+ 86.Kf2 Rd1 87.Bb3 Rd6 88.h4 Kg7 89.c4 Bxe6 90.c5 Rxd7 91.Bxe6 Rc7 92.Ke3 -+ (-2.34) Depth: 16/45 00:02:32 247094kN 83...Bf5 84.d6 Re4 85.d7 Re1+ 86.Kf2 Rd1 87.Bb3 Rd6 88.h4 Kg7 89.c4 Bxe6 90.c5 Rxd7 91.Bxe6 Rc7 92.Ke3 -+ (-2.34) Depth: 16/45 00:03:23 330464kN 83...Bf5 84.d6 Re4 85.Bd5 Re5 86.e7 Bd7 87.c4 Rxd5 88.cxd5 Kg7 89.Kf2 Kf6 90.Kg3 Ke5 91.Kh4 Kxd6 -+ (-2.54) Depth: 17/45 00:05:01 489333kN 83...Bf5 84.d6 Re4 85.Bd5 Re5 86.e7 Bd7 87.c4 Rxd5 88.cxd5 Kg7 89.Kf2 Kf6 90.Kg3 Ke5 91.Kh4 Kxd6 -+ (-2.54) Depth: 17/46 00:07:05 690566kN 83...Bf5 84.d6 Re4 85.Bd5 Re5 86.e7 Bd7 87.c4 Rxd5 88.cxd5 Kg7 89.Kf2 Kf6 90.Kg3 Ke5 91.Kh4 Kxd6 92.Kg5 Be8 93.Kf6 -+ (-2.91) Depth: 18/49 00:10:55 1060362kN (, MyTown 06.12.2004) Uri
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