Author: Robert Hyatt
Date: 13:13:05 07/17/04
Go up one level in this thread
On July 17, 2004 at 13:38:05, Roy Brunjes wrote: >On July 16, 2004 at 21:38:13, Robert Hyatt wrote: > >>On July 16, 2004 at 16:17:59, Rémi Coulom wrote: >> >>>Hi, >>> >>>This position is taken from the ParSOS - The Crazy Bishop game: >>>[D]8/p6p/1p2kBp1/2p5/2P5/P4P2/P3nK1P/8 b - - >>> >>>During the game, GM Boris Alterman commented that Kxf6 Kxe2 leads to a won pawn >>>endgame for black. My program does not manage to evaluate this pawn endgame as a >>>win, even after a very long search. Can you explain if/how it is a win ? >>> >>>TCB Played Nc1 during the game (at move 43). This is the whole game: >>> >>>[Event "WCCC2004"] >>>[Site "Bar-Ilan"] >>>[Date "2004.07.11"] >>>[Round "9"] >>>[White "ParSOS"] >>>[Black "The Crazy Bishop"] >>>[Result "1/2-1/2"] >>> >>>1. e4 e5 2. Nf3 Nc6 3. c3 d5 4. Bb5 dxe4 5. Nxe5 Qd5 6. Qa4 Ne7 7. Nxc6 Nxc6 8. >>>O-O Bd7 9. Re1 O-O-O 10. Bf1 f5 11. Na3 Kb8 12. Qc4 Be6 13. Qxd5 Bxd5 14. d4 >>>exd3 15. Bg5 Bxa3 16. bxa3 Rd7 17. Bxd3 Bxg2 18. Re3 Be4 19. Bxe4 fxe4 20. Rxe4 >>>Rf8 21. Rae1 b6 22. Kf1 Rf5 23. Bc1 Kb7 24. Ke2 Ne7 25. Kf1 Nd5 26. c4 Nf6 27. >>>Re7 Kc8 28. R1e2 Kd8 29. Rxd7+ Kxd7 30. Bb2 Rf4 31. Rd2+ Ke6 32. Re2+ Kf7 33. >>>Rc2 Rf5 34. Bc1 g6 35. Kg2 Ne4 36. Kf1 c5 37. Kg2 Nd6 38. f3 Ke6 39. Kg3 Rf6 >>>40. Bb2 Nf5+ 41. Kf2 Nd4 42. Re2+ Nxe2 43. Bxf6 Nc1 44. Bg7 Nxa2 45. Ke3 Nc1 >>>46. Kf4 Nd3+ 47. Ke4 Nf2+ 48. Kf4 h5 49. Kg5 Kf7 50. Be5 Nh3+ 51. Kh4 Ng1 52. >>>Kg3 Ne2+ 53. Kf2 Nd4 54. Ke3 Nc6 55. Bc3 Ke6 56. Ke4 Nd8 57. f4 h4 58. h3 Nf7 >>>59. Be1 Nd6+ 60. Kd3 Kf5 61. Bxh4 Kxf4 62. Bd8 Nf7 63. Bc7+ Ne5+ 64. Kc3 Ke4 >>>65. Bd8 Nc6 66. Bg5 Nd4 67. h4 Ke5 68. Kd3 Kf5 69. a4 Nc6 70. Kd2 Ke4 71. Bf6 >>>Nd4 72. Kc3 Ke3 73. Be5 Ke4 74. Bf6 Nc6 75. Kd2 Kf5 76. Bg5 Ne5 77. Kc3 Kg4 78. >>>Be7 Nc6 79. Bf6 Kf5 80. Bg5 Ke4 81. Bf6 Nd4 82. Kd2 Kf5 83. Bd8 Ke4 84. Bf6 Kf5 >>>85. Bd8 Kf4 86. Bf6 Nc6 87. Kc3 Ke3 88. Bg7 Ke4 89. Bf6 Ke3 90. Bg7 Kf2 91. Kb2 >>>Kf3 92. Kc3 Kg3 93. Bf6 Kf4 94. Kd3 Kf5 95. Bg5 Ne5+ 96. Kc3 Kg4 97. Be7 Nc6 >>>98. Bf6 Kf5 99. Bg5 Na5 100. Bd8 Ke4 101. Bf6 Kf3 102. Kd3 Nc6 103. Kd2 Na5 >>>104. Kd3 Kg4 105. Be7 Kf4 106. Bd8 Ke5 107. Bc7+ Kf5 108. Bd8 Nc6 109. Bg5 Nd4 >>>110. Ke3 Nb3 111. Bd8 Ke6 112. Bc7 Na5 113. Kd3 Kf5 114. Bd8 Kf4 115. Bf6 Kg4 >>>116. Be7 Kg3 117. Bf6 Kf4 118. Bd8 g5 119. Bxg5+ Kg4 120. Bf6 Kf5 121. Bg7 Nc6 >>>122. Bc3 Kg4 123. Bf6 Kf5 124. Ba1 Ne7 125. Kd2 Ng6 126. h5 Ne7 127. Bg7 Kg5 >>>128. Bf8 Nf5 129. a5 Nd4 130. h6 Kg6 131. a6 Nc6 132. Kd3 Nb4+ 133. Ke4 Nxa6 >>>134. Kd5 Nb4+ 135. Kd6 Nc2 136. Kc7 Nd4 137. Bg7 Ne6+ 138. Kb7 Nxg7 139. hxg7 >>>Kxg7 140. Kxa7 1/2-1/2 >>> >>>In fact, Boris Alterman commented almost all the way to move 70 that it should >>>be a win for black. There was probably a way to win this game, but I do not what >>>it was. comments would be appreciated. >>> >>>Rémi >> >>All of white's pawns are weak. Getting rid of the pieces lets black infiltrate >>on one side or the other. Crafty on the quad opteron: >> >> 17 8.62 -1.24 1. ... Kxf6 2. Kxe2 Kg5 3. Kf2 Kf4 >> 4. Ke2 g5 5. Kf2 g4 6. fxg4 Kxg4 7. >> a4 Kf4 8. Ke2 Ke4 9. a5 bxa5 10. h4 >> (s=4) >> 17-> 16.41 -1.24 1. ... Kxf6 2. Kxe2 Kg5 3. Kf2 Kf4 >> 4. Ke2 g5 5. Kf2 g4 6. fxg4 Kxg4 7. >> a4 Kf4 8. Ke2 Ke4 9. a5 bxa5 10. h4 >> (s=4) >> 18 19.49 -1.29 1. ... Kxf6 2. Kxe2 Kg5 3. Kf2 Kf4 >> 4. a4 g5 5. a3 g4 6. fxg4 Kxg4 7. Ke3 >> Kh3 8. a5 h5 9. axb6 axb6 10. Kf4 Kxh2 >> 11. Ke5 (s=3) >> 18-> 39.31 -1.29 1. ... Kxf6 2. Kxe2 Kg5 3. Kf2 Kf4 >> 4. a4 g5 5. a3 g4 6. fxg4 Kxg4 7. Ke3 >> Kh3 8. a5 h5 9. axb6 axb6 10. Kf4 Kxh2 >> 11. Ke5 (s=4) >> 19 43.72 -1.27 1. ... Kxf6 2. Kxe2 Kg5 3. Kf2 Kf4 >> 4. a4 g5 5. a3 h5 6. Ke2 g4 7. fxg4 >> Kxg4 8. Kf2 Kf4 9. a5 bxa5 <HT> (s=3) > >Bob, > >I downloaded Crafty 19.15 from the ChessBase site and ran it under the Shredder >8 GUI with 256 MB of hash. Here is the analysis it produces for this position >in infinite analysis mode: > >New game, >8/p6p/1p2kBp1/2p5/2P5/P4P2/P3nK1P/8 b - - 0 1 > >Analysis by Crafty 19.15: > >1...Kxf6 2.Kxe2 Ke5 3.Ke3 g5 4.a4 h6 > µ (-1.18) Depth: 1/5 00:00:00 >1...Kxf6 2.Kxe2 Ke5 3.Ke3 g5 4.a4 h6 > µ (-1.18) Depth: 8/12 00:00:00 >1...Kxf6 2.Kxe2 Ke5 3.Ke3 g5 4.a4 h6 > µ (-1.18) Depth: 8/12 00:00:00 >1...Kxf6 2.Kxe2 Ke5 3.Ke3 g5 4.a4 h6 > µ (-1.18) Depth: 8/12 00:00:00 >1...Kxf6 2.Kxe2 Ke5 3.Ke3 g5 4.a4 h6 > µ (-1.18) Depth: 8/12 00:00:00 >1...Kxf6 2.Kxe2 Ke5 3.Ke3 g5 4.a4 h6 > µ (-1.18) Depth: 8/12 00:00:00 >1...Kxf6 2.Kxe2 Ke5 3.Ke3 g5 4.a4 h6 > µ (-1.18) Depth: 8/12 00:00:00 8kN >1...Kxf6 2.Kxe2 Ke5 3.Ke3 g5 4.a4 h6 > µ (-1.18) Depth: 8/12 00:00:00 8kN >1...Kxf6 2.Kxe2 g5 3.Ke3 Kf5 4.a4 Ke5 5.h3 > µ (-1.12) Depth: 8/12 00:00:00 19kN >1...Kxf6 2.Kxe2 g5 3.Ke3 Ke5 4.a4 Kf5 5.h3 Ke5 > µ (-1.12) Depth: 9/14 00:00:00 48kN >1...Nd4 2.Bxd4 cxd4 3.a4 g5 4.h3 Ke5 5.Ke2 Kf4 6.Kd3 > µ (-1.14) Depth: 9/14 00:00:00 132kN >1...Nd4 2.Bxd4 cxd4 3.Ke2 Kf5 4.Kd3 Kf4 5.Kxd4 Kxf3 6.h4 Kf4 > µ (-1.08) Depth: 10/16 00:00:00 238kN >1...Kxf6 2.Kxe2 g5 3.Ke3 Ke5 4.a4 Kf5 5.h3 Ke5 6.a3 > µ (-1.09) Depth: 10/16 00:00:00 260kN >1...Kxf6 2.Kxe2 g5 3.Ke3 Kf5 4.a4 Ke5 5.h3 Kf5 6.a3 Ke5 > µ (-1.09) Depth: 11/17 00:00:00 402kN >1...Kxf6 2.Kxe2 g5 3.Ke3 Kf5 4.a4 Ke5 5.h3 Kf5 6.a3 Ke5 7.Kd3 > µ (-1.09) Depth: 12/20 00:00:01 719kN >1...Kxf6 2.Kxe2 g5 3.Ke3 Kf5 4.a4 Ke5 5.h3 Kf5 6.a3 Ke5 7.Kd3 Kf4 > µ (-1.09) Depth: 13/22 00:00:01 1530kN >1...Kxf6 2.Kxe2 Kg5 3.Kf2 Kh4 4.a4 Kg5 5.Ke3 > µ (-1.08) Depth: 14/24 00:00:04 4147kN >1...Kxf6 2.Kxe2 Kg5 3.Kf2 Kh4 4.Kg2 h6 5.a4 Kg5 6.Kg3 Kf5 7.Kf2 h5 8.Ke3 Ke5 > µ (-1.06) Depth: 15/26 00:00:09 10070kN >1...Kxf6 2.Kxe2 Kg5 3.Kf2 h6 4.a4 Kf4 5.Ke2 a6 6.Kf2 h5 7.h4 g5 8.hxg5 Kxg5 >9.Ke3 Kf5 > µ (-1.06) Depth: 16/27 00:00:20 23158kN >1...Kxf6 2.Kxe2 Kg5 3.Kf1 Kf4 4.Kf2 g5 5.a4 g4 6.fxg4 Kxg4 7.a3 Kf4 8.Ke2 Ke4 >9.a5 bxa5 10.h4 > µ (-1.21) Depth: 17/30 00:00:51 60449kN >1...Kxf6 2.Kxe2 Kg5 3.a4 Kf4 4.Kf2 g5 5.a3 g4 6.fxg4 Kxg4 7.Ke3 Kh3 8.a5 h5 >9.axb6 axb6 10.Kf4 Kxh2 11.Ke5 > µ (-1.29) Depth: 18/31 00:01:47 124562kN >1...Nd4 2.Bxd4 cxd4 3.Ke2 g5 4.Kd3 Ke5 > -+ (-1.41) Depth: 18/31 00:05:11 369527kN >1...Nd4 2.Bxd4 cxd4 3.Ke2 g5 4.Kd3 Ke5 5.a4 a5 6.a3 h5 7.Kd2 Kf4 8.Kd3 > -+ (-1.46) Depth: 19/35 00:06:40 476485kN >1...Nd4 2.Bh8 Nf5 3.Ke2 Nd6 4.Kd3 Kf5 5.Bc3 Kf4 6.a4 Kxf3 7.Be5 Ne4 8.Bb8 Nf6 >9.Bxa7 Nd7 10.a5 bxa5 11.h3 > -+ (-1.70) Depth: 20/37 00:33:37 2472812kN > >(Brunjes, My Town 17.07.2004) > >Why should the same engine give such different analysis? I know the quad >Opterons are hugely faster than my 1.5 GHz Centrino, but on my machine at ply >18, 19 and 20 Crafty 19.15 prefers Nd4 to Kxf6 which is different from the same >depth search on the quad Opterons. > >Curious, > >Roy Evaluation is slightly different for "analysis mode" as opposed to "game mode". The asymmetry is almost completely disabled in analysis mode.
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