Why did Rybka lose?

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kingliveson
Posts: 1388
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Real Name: Franklin Titus
Location: 28°32'1"N 81°22'33"W

Why did Rybka lose?

Post by kingliveson » Sun Oct 31, 2010 4:09 am

Ponder on game: Move 157 ??

[Event "IvanHoe vs Rybka, Blitz 5m+3s"]
[Site "W0111D0001"]
[Date "2010.10.30"]
[Round "3"]
[White "IvanHoe 9.50b x64"]
[Black "Deep Rybka 4 SSE42 x64"]
[Result "1-0"]
[ECO "B12"]
[Annotator "0.32;0.21"]
[PlyCount "369"]
[TimeControl "300+3"]

{AMD Phenom(tm) II X4 940 Processor 3010 MHz W=23.9 plies; 3,569kN/s; 9,768,
614 TBAs B=20.1 plies; 206kN/s; 280 TBAs} 1. e4 c6 2. d4 d5 3. e5 Bf5 4. Nf3
e6 {Both last book move} 5. Nc3 {0.32/19 20} Bb4 {0.21/18 21} 6. Bd3 {0.29/22 0
} Ne7 {0.20/18 14} 7. O-O {0.29/22 0} Nd7 {0.19/17 16 (Bxd3)} 8. Ne2 {0.30/20
11} O-O {0.20/17 0} 9. c3 {0.30/21 32} Ba5 {0.18/18 0} 10. Bg5 {0.30/20 6 (h3)}
Bxd3 {0.13/17 23} 11. Qxd3 {0.26/20 0} h6 {0.13/17 10} 12. Bxe7 {0.27/19 0}
Qxe7 {0.11/17 25} 13. h3 {0.21/20 0 (Qe3)} c5 {0.08/16 41 (Rfc8)} 14. Rfc1 {0.
19/20 37 (Rfd1)} Rfc8 {0.06/15 18 (Bb6)} 15. Rc2 {0.15/19 22 (Qe3)} c4 {-0.07/
18 21 (Bb6)} 16. Qd1 {0.06/20 17 (Qd2)} b5 {-0.08/18 17 (Bc7)} 17. b4 {0.05/20
21 (Rcc1)} Bd8 {-0.15/18 13} 18. a4 {0.02/23 0} a5 {-0.20/19 10} 19. Rb2 {0.00/
24 0} bxa4 {-0.19/20 20 (axb4)} 20. Rxa4 {0.00/21 10} axb4 {-0.19/21 0} 21.
Rbxb4 {0.00/22 11 (Raxb4)} Nb6 {-0.21/19 13} 22. Rxa8 {0.00/24 0} Rxa8 {-0.22/
21 15} 23. Qb1 {-0.05/24 0} Qa7 {-0.22/20 6} 24. Qc1 {-0.05/22 0} Qb7 {-0.24/
20 17 (Nd7)} 25. Qb2 {-0.07/24 25 (Qb1)} Ra6 {-0.28/20 12} 26. Ne1 {-0.09/25 0
(g3)} Qa8 {-0.28/20 19 (Qa7)} 27. Nc2 {-0.20/23 13} Ra4 {-0.18/18 4} 28. Kf1 {
-0.05/23 7} Ra2 {-0.20/18 0 (Rxb4)} 29. Qb1 {0.00/23 11} Ra7 {-0.17/19 0 (Nd7)}
30. Kg1 {0.00/23 16 (g3)} Bc7 {-0.19/18 17 (Qc6)} 31. g3 {0.00/21 12} Nc8 {-0.
21/18 2} 32. Rb5 {0.00/22 3 (Rb2)} Ne7 {-0.21/18 13} 33. Kg2 {0.00/23 0 (Rb2)}
Nc6 {-0.31/14 7} 34. Nc1 {-0.04/21 6 (Rc5)} h5 {-0.31/16 15} 35. h4 {-0.04/21 0
} g6 {-0.31/16 7 (f6)} 36. Kh2 {0.00/21 11 (Kg1)} Kg7 {-0.31/16 4 (Na5)} 37.
Kg2 {0.00/20 4 (Ne2)} Kh7 {-0.31/13 3 (Kg8)} 38. f3 {0.00/21 9 (Kg1)} Kg7 {-0.
31/16 4} 39. Ne2 {0.00/20 0} Na5 {-0.31/15 3} 40. Nc1 {0.00/21 0} Qf8 {-0.29/
15 3 (Nc6)} 41. Rb2 {-0.07/20 22 (Ne3)} Qe8 {-0.24/15 5 (Qe7)} 42. Na3 {0.00/
21 14 (Nb4)} Ra6 {-0.14/14 3 (Nb3)} 43. Nb5 {0.00/21 6} Bb8 {-0.08/17 0 (Qc6)}
44. Ra2 {0.00/22 7} Qc6 {-0.12/18 0} 45. Ra1 {-0.04/22 21 (Qb2)} Qb7 {-0.29/19
8} 46. Qb2 {-0.05/24 0} Nc6 {-0.29/19 5} 47. Rxa6 {-0.06/24 0} Qxa6 {-0.29/19 4
} 48. Na3 {-0.06/24 0} Qa4 {-0.29/18 4} 49. Nc2 {-0.07/23 4} Bc7 {-0.32/19 0}
50. Ne3 {-0.10/22 14} Na7 {-0.35/19 0} 51. Qd2 {-0.18/23 6} Nb5 {-0.41/19 0}
52. Ne2 {-0.12/23 5} Qb3 {-0.41/19 0} 53. Nd1 {-0.20/23 14} Bd8 {-0.41/21 0}
54. Kf1 {-0.21/23 7 (Kf2)} Qb1 {-0.43/19 5 (Ba5)} 55. Kf2 {-0.22/23 4} Ba5 {-0.
43/18 0} 56. Ke3 {-0.37/22 9 (Nb2)} Bb6 {-0.54/18 7} 57. Nb2 {-0.38/23 0 (f4)}
Qf5 {-0.54/17 6} 58. f4 {-0.37/23 0} Ba5 {-0.54/18 7 (Qb1)} 59. Kf2 {-0.37/22 3
} Qe4 {-0.54/18 1 (Qb1)} 60. Nd1 {-0.37/23 7} Qb1 {-0.54/19 0} 61. Ke3 {-0.37/
22 2} Kf8 {-0.54/19 2 (Qb3)} 62. Kf2 {-0.37/24 6 (Nf2)} Ke7 {-0.54/17 5 (Kg8)}
63. Nb2 {-0.37/22 5 (Ke3)} Qa2 {-0.54/18 5} 64. Kf3 {-0.37/23 0 (Ke3)} Kf8 {-0.
54/18 5} 65. Ke3 {-0.37/23 0} Qb1 {-0.54/19 6 (Bb6)} 66. Nd1 {-0.37/22 4} Kg7 {
-0.52/18 0 (Kg8)} 67. Kf2 {-0.37/22 3} Kg8 {-0.54/18 1} 68. Ke3 {-0.37/24 10}
Kh7 {-0.52/19 0} 69. Kf2 {-0.37/23 6} Kh8 {-0.52/20 0 (Qb3)} 70. Ke3 {-0.37/23
6} Kg8 {-0.50/19 2} 71. Kf2 {-0.37/22 1} Kh7 {-0.50/18 5 (Qb3)} 72. Ke3 {-0.37/
22 4} Kh8 {-0.50/17 3 (Qb3)} 73. Kf2 {-0.22/18 2} f5 {-0.50/18 2 (Bd8)} 74. Ke3
{-0.21/21 3} Kg7 {-0.50/19 1 (Kg8)} 75. Kf2 {-0.21/23 5 (Nf2)} Kg8 {-0.50/20 6
(Kf7)} 76. Ke3 {-0.21/23 4 (Ne3)} Kf7 {-0.50/19 4} 77. Kf2 {-0.21/24 0 (Nf2)}
Ke7 {-0.50/20 5} 78. Ke3 {-0.21/24 0 (Nb2)} Kf8 {-0.50/20 7} 79. Kf2 {-0.21/26
0 (Nf2)} Kf7 {-0.50/20 5 (Qb3)} 80. Ke3 {-0.21/24 7 (Ne3)} Ke7 {-0.50/19 4
(Qb3)} 81. Nf2 {-0.21/23 4} Kf8 {-0.50/20 0 (Qb3)} 82. Nd1 {-0.21/24 4} Ke8 {
-0.50/20 0 (Qb3)} 83. Kf2 {-0.21/23 3 (Nf2)} Kd7 {-0.50/20 5} 84. Ke3 {-0.21/
24 0} Kc6 {-0.50/20 6 (Qb3)} 85. Kf2 {-0.21/22 2 (Nf2)} Kb7 {-0.50/20 4 (Kc7)}
86. Kg2 {-0.21/23 4 (Ke3)} Kc7 {-0.50/17 3} 87. Kf2 {-0.21/24 3 (Nf2)} Kc6 {-0.
50/19 3} 88. Ke3 {-0.21/24 0} Kb6 {-0.50/19 4 (Kd7)} 89. Kf2 {-0.21/24 3 (Nb2)}
Kc7 {-0.50/18 2 (Qb3)} 90. Ke3 {-0.21/24 4} Kc8 {-0.50/21 0 (Kd7)} 91. Kf2 {-0.
21/24 2 (Nf2)} Kd8 {-0.43/21 6 (Qb3)} 92. Kg2 {-0.21/22 2 (Ke3)} Ke7 {-0.43/18
2} 93. Kf2 {-0.21/23 0} Qb3 {-0.43/20 3 (Bb6)} 94. Nc1 {-0.21/24 2 (Kf3)} Qa3 {
-0.43/20 3} 95. Ne2 {-0.21/26 0} Kf7 {-0.43/21 3 (Qa4)} 96. Qc2 {-0.21/23 4}
Kg7 {-0.43/20 0} 97. Qb1 {-0.21/24 5 (Kf3)} Qa4 {-0.43/20 6} 98. Kg2 {-0.21/25
0 (Ke3)} Kf7 {-0.43/19 4 (Bb6)} 99. Kf2 {-0.21/23 5 (Kf3)} Ke7 {-0.43/18 2
(Bd8)} 100. Kf3 {-0.21/21 2 (Qc1)} Bd8 {-0.43/19 4 (Bb6)} 101. Ne3 {-0.21/22 3}
Bb6 {-0.43/19 0 (Qb3)} 102. Qc1 {-0.21/23 4} Ba5 {-0.43/21 0} 103. Qd2 {-0.21/
23 3 (Nd1)} Qb3 {-0.43/20 3 (Qa3)} 104. Nd1 {-0.21/24 2} Kf7 {-0.43/21 2} 105.
Qc1 {-0.21/25 3} Qa2 {-0.43/21 1 (Bb6)} 106. Kf2 {-0.21/25 6 (Ke3)} Kg7 {-0.43/
20 4} 107. Kf3 {-0.21/26 0 (Ke3)} Kh6 {-0.43/19 4 (Kg8)} 108. Nf2 {-0.21/23 4}
Qa4 {-0.43/18 0 (Bd8)} 109. Nd1 {-0.21/23 7 (Qb2)} Kg7 {-0.42/18 7} 110. Qd2 {
-0.21/25 0 (Qb1)} Qb3 {-0.43/20 4} 111. Kf2 {-0.21/25 0 (Qc1)} Kh6 {-0.43/19 3
(Qa3)} 112. Kf3 {-0.21/24 3 (Qc1)} Kh7 {-0.43/18 3 (Qb1)} 113. Qc1 {-0.21/24 4}
Qa2 {-0.43/21 0} 114. Ke3 {-0.21/25 11} Kg8 {-0.43/21 0} 115. Kf3 {-0.21/25 9}
Kg7 {-0.43/22 0} 116. Kf2 {-0.16/23 7} Kh6 {-0.43/21 9} 117. Kf3 {0.00/25 0}
Na3 {-0.04/18 9 (Kg7)} 118. Kf2 {0.00/25 4 (Qb2)} Kg7 {-0.05/17 2 (Nb5)} 119.
Qb2 {0.00/26 5} Qxb2 {-0.30/24 0 (Qb3)} 120. Nxb2 {0.00/28 3} Nb1 {-0.30/27 1}
121. Na4 {0.00/29 1 (Nd1)} Nd2 {-0.37/25 4} 122. Nc5 {0.00/30 0 (Ke3)} Ne4+ {
-0.37/26 5 (Kf7)} 123. Nxe4 {0.00/28 4} dxe4 {-0.37/28 0} 124. Ke3 {0.00/29 2}
Kf8 {-0.37/26 2 (Kf7)} 125. Kd2 {0.00/28 2} Ke7 {-0.37/24 2} 126. Ke3 {0.00/30
0 (Nc1)} Kd7 {-0.37/28 5} 127. Kd2 {0.00/30 0} Kc6 {-0.37/28 6 (Ke7)} 128. Ke3
{0.00/30 3} Kd5 {-0.37/28 1 (Kd7)} 129. Kd2 {0.00/32 5} Bc7 {-0.37/27 0 (Kc6)}
130. Ke3 {0.00/29 5} Kc6 {-0.37/28 0 (Ba5)} 131. Ng1 {0.00/28 2 (Kd2)} Kb5 {-0.
37/25 4 (Kd5)} 132. Kd2 {0.00/28 3} Ba5 {-0.37/25 0} 133. Ne2 {0.00/29 2} Kb6 {
-0.37/26 6 (Kc6)} 134. Ke3 {0.00/28 4} Ka6 {-0.37/25 0 (Kc6)} 135. Kf2 {0.00/
26 4} Bb6 {-0.37/27 0 (Kb5)} 136. Ke3 {0.00/29 4} Kb5 {-0.37/27 0 (Ba5)} 137.
Kd2 {0.00/28 3 (Nc1)} Ba5 {-0.37/26 9 (Kc6)} 138. Ke3 {0.00/27 3} Kb6 {-0.37/
26 1 (Kc6)} 139. Kf2 {0.00/27 3} Kc7 {-0.37/28 1 (Kc6)} 140. Ke3 {0.00/30 3}
Kc6 {-0.37/28 1 (Kd7)} 141. Kd2 {0.00/29 2 (Kf2)} Kd5 {-0.37/28 6 (Kd7)} 142.
Ke3 {0.00/30 2} Bd8 {-0.37/29 2 (Kc6)} 143. Nc1 {0.00/27 2 (Kf2)} Be7 {-0.37/
25 6 (Ba5)} 144. Ne2 {0.00/30 9 (Na2)} Bf8 {-0.37/29 5 (Bd8)} 145. Nc1 {0.00/
32 2 (Kf2)} Ba3 {-0.37/25 8 (Be7)} 146. Ne2 {0.00/30 2} Kc6 {-0.37/28 2 (Bf8)}
147. Kd2 {0.00/28 2} Be7 {-0.37/26 5 (Bb2)} 148. Ke3 {0.00/30 4 (Nc1)} Bf8 {-0.
37/28 6 (Kd5)} 149. Ng1 {0.00/29 3 (Kd2)} Ba3 {0.00/24 3 (Kd5)} 150. Kd2 {0.00/
30 6} Kd5 {-0.37/26 0 (Bb2)} 151. Ne2 {0.00/31 6} Kc6 {0.00/27 0 (Bb2)} 152.
Ng1 {0.00/30 2} Kc7 {0.00/26 4 (Bb2)} 153. Nh3 {0.00/28 4} Bb2 {0.00/27 0} 154.
Kc2 {0.00/28 4} Ba3 {0.00/26 0} 155. Ng5 {0.00/28 3 (Kd2)} Kd7 {0.00/27 4} 156.
Kd2 {0.00/29 0} Bb2 {0.00/27 8} 157. Kc2 {0.00/28 0} Ba1 {0.00/26 4 (Ba3)} 158.
Nh3 {2.31/23 6 (Kd2)} Kc7 {2.86/16 4} 159. Ng1 {3.03/24 0} Kc6 {2.87/20 5} 160.
Ne2 {3.41/25 0} Kd5 {2.87/21 4} 161. Kc1 {3.49/25 0 (Kb1)} Bxc3 {2.94/20 5}
162. Nxc3+ {3.49/25 0} Kxd4 {2.94/20 4} 163. Kd2 {3.49/26 0} Kc5 {5.76/18 4}
164. Ne2 {3.65/25 0} Kc6 {5.76/18 2 (Kd5)} 165. Nd4+ {5.98/20 6 (Kc3)} Kd5 {5.
76/21 4 (Kd7)} 166. Kc3 {7.13/20 3} e3 {5.76/17 0} 167. Nf3 {7.13/21 2} e2 {10.
52/18 1 (Kc5)} 168. Kd2 {8.02/21 2} Kc6 {10.52/20 1 (e1R)} 169. Kxe2 {8.28/23 2
} Kd7 {10.59/21 1 (c3)} 170. Kd2 {12.24/25 11} Kc6 {13.42/17 0 (Ke8)} 171. Nd4+
{15.37/19 9} Kd5 {13.42/16 0 (Kc7)} 172. Kc3 {18.85/19 3} Kc5 {#23/15 1} 173.
Nxe6+ {19.66/18 1} Kc6 {#13/15 3} 174. Nf8 {26.09/19 0 (Nd4+)} Kc7 {#14/14 9}
175. Kxc4 {#14/22 0} Kc6 {28.77/14 4 (Kd8)} 176. Nxg6 {#13/22 5 (Ne6)} Kd7 {#9/
19 4 (Kc7)} 177. Kd5 {#9/24 4} Kc7 {#8/18 0 (Kc8)} 178. e6 {#9/22 4} Kc8 {#7/
18 0 (Kd8)} 179. Kd6 {#7/22 7 (Ne5)} Kd8 {#6/17 8} 180. e7+ {#6/24 0} Ke8 {#5/
17 7} 181. g4 {#5/25 0} Kf7 {#4/16 4 (hxg4)} 182. Ne5+ {#4/22 6} Kg8 {#3/14 0
(Ke8)} 183. e8=Q+ {#3/18 2} Kh7 {#2/14 2} 184. Qg6+ {#2/18 0} Kh8 {#1/14 0}
185. Nf7# {#1/125 0} 1-0
PAWN : Knight >> Bishop >> Rook >>Queen

ernest
Posts: 247
Joined: Thu Sep 02, 2010 10:33 am

Re: Why did Rybka lose?

Post by ernest » Sun Oct 31, 2010 2:38 pm

In infinite analysis, DR4 needs a few minutes before discovering that 157... Ba1 is bad

Analysis by Deep Rybka 4 w32: (2-cores)
157...Ba1 158.Nf7 Kc6 159.Nd6[] Kd5 160.Nb5[] e3 161.Kd1[] Kc6 162.Na7+ Kd5 163.Nb5[] Kc6 164.Na7+ Kd5 165.Nb5[] Kc6 166.Na7+ Kd5 167.Nb5[] Kc6 168.Na7+ Kd5 169.Nb5[] Kc6 170.Na7+ Kd5 171.Nb5[] Kc6 172.Na7+ Kd5
= (0.00) Depth: 28 00:00:45 6055kN
157...Ba3
= (0.00) Depth: 29 00:02:56 23826kN, tb=115

User avatar
robbolito
Posts: 601
Joined: Thu Jun 10, 2010 3:48 am

Re: Why did Rybka lose?

Post by robbolito » Tue Nov 02, 2010 12:45 am

[Event "Blitz:10'"]
[Site "Milwaukee"]
[Date "2010.10.31"]
[Round "1"]
[White "IvanHoe T50K.x64POPCNT"]
[Black "Rybka 3.x64"]
[Result "1-0"]
[ECO "D43"]
[WhiteElo "3190"]
[BlackElo "3190"]
[Annotator "0.05;-0.23"]
[PlyCount "89"]
[TimeControl "600"]

1. c4 {B/0 0} Nf6 {B/0 0} 2. d4 {B/0 0} c6 {B/0 0} 3. Nc3 {B/0 0} d5 {B/0 0} 4.
Nf3 {B/0 0} e6 {B/0 0} 5. Bg5 {B/0 0} h6 {B/0 0} 6. Bh4 {B/0 0} dxc4 {B/0 0} 7.
e4 {B/0 0} g5 {B/0 0} 8. Bg3 {B/0 0} b5 {B/0 0} 9. Be2 {B/0 0} Bb7 {B/0 0} 10.
h4 {B/0 0} g4 {Both last book move B/0 0} 11. Ne5 {0.05/21 53} h5 {-0.23/13 11}
12. O-O {0.08/20 32} Nbd7 {-0.13/12 9} 13. Qc2 {0.00/19 6} Nxe5 {-0.05/14 32}
14. Bxe5 {0.00/19 11} Rg8 {(Bf8-h6) -0.09/14 5} 15. Rfd1 {0.13/19 7} Rg6 {-0.
05/15 24} 16. Bf1 {(Be5-f4) 0.09/20 17} a6 {(Nf6-d7) -0.06/13 7} 17. a4 {0.09/
21 60} Nd7 {-0.05/13 17} 18. Bg3 {0.03/20 3} Qb6 {(Nd7-b6) 0.00/15 14} 19. Ne2
{(e4-e5) 0.01/20 32} Be7 {(Bf8-g7) -0.06/13 8} 20. Nf4 {0.00/20 15} Rh6 {-0.11/
14 7} 21. Qd2 {(Nf4-e2) 0.00/20 6} Rh8 {(Rh6-h7) -0.22/14 7} 22. Qe3 {-0.05/20
76} e5 {(Ra8-d8) -0.28/13 9} 23. Ne2 {-0.07/18 2} Bf6 {-0.29/14 5} 24. Rd2 {
(a4-a5) -0.07/19 11} O-O-O {-0.08/14 12} 25. b3 {0.00/18 2} Bg7 {-0.08/14 14}
26. Rdd1 {0.16/17 2} c5 {0.12/14 17} 27. d5 {0.19/17 2} cxb3 {0.23/15 10} 28.
axb5 {0.24/18 3} b2 {(a6xb5) 0.33/16 17} 29. Rab1 {0.35/19 2} axb5 {0.33/16 5}
30. Nc3 {(Rb1xb2) 0.37/19 2} Bh6 {0.47/15 13} 31. Qd3 {(Qe3-e1) 0.28/18 2} b4 {
0.35/14 5} 32. Na4 {0.46/21 14} Qd6 {(Qb6-a5) 0.43/15 7} 33. Qc2 {0.50/21 10}
f6 {(Bh6-c1) 0.36/14 3} 34. Nxb2 {(Bf1-b5) 0.95/20 9} Kb8 {(Bh6-f8) 0.74/14 5}
35. Nc4 {1.67/18 2} Qc7 {0.83/14 5} 36. Ra1 {(Bg3-h2) 1.67/16 0} Rdg8 {2.40/13
49} 37. d6 {(Qc2-a4) 4.67/17 7} Qc6 {4.89/13 13} 38. Qa2 {4.67/15 0} Qxe4 {5.
15/13 35} 39. Qa5 {(Qa2-a7+) 5.28/17 2} Qc6 {7.48/12 35} 40. Qa7+ {5.28/16 0}
Kc8 {3.95/9 0} 41. Na5 {5.88/18 2} Qb6 {3.95/9 0} 42. Nxb7 {5.88/17 0} Qxa7 {
7.80/13 14} 43. Rxa7 {6.07/17 2} Kb8 {7.83/12 12} 44. Rda1 {6.07/15 0} Rg7 {7.
83/11 8} 45. Nxc5 {8.25/17 3} 1-0

hyatt
Posts: 1242
Joined: Thu Jun 10, 2010 2:13 am
Real Name: Bob Hyatt (Robert M. Hyatt)
Location: University of Alabama at Birmingham
Contact:

Re: Why did Rybka lose?

Post by hyatt » Wed Nov 03, 2010 1:15 am

ernest wrote:In infinite analysis, DR4 needs a few minutes before discovering that 157... Ba1 is bad

Analysis by Deep Rybka 4 w32: (2-cores)
157...Ba1 158.Nf7 Kc6 159.Nd6[] Kd5 160.Nb5[] e3 161.Kd1[] Kc6 162.Na7+ Kd5 163.Nb5[] Kc6 164.Na7+ Kd5 165.Nb5[] Kc6 166.Na7+ Kd5 167.Nb5[] Kc6 168.Na7+ Kd5 169.Nb5[] Kc6 170.Na7+ Kd5 171.Nb5[] Kc6 172.Na7+ Kd5
= (0.00) Depth: 28 00:00:45 6055kN
157...Ba3
= (0.00) Depth: 29 00:02:56 23826kN, tb=115

??

0.00 is not "bad". It is "draw". Post was about "losing".

User avatar
Uly
Posts: 838
Joined: Thu Jun 10, 2010 5:33 am

Re: Why did Rybka lose?

Post by Uly » Wed Nov 03, 2010 2:25 am

157...Ba1 fails low (at depth 29) and Rybka finds that 157...Ba3 is better. I hate how Rybka doesn't tell the user about the fail low, that's why the "Always score main move" and "Display upperbounds" options were added, it would force Rybka to show the fail low to the user and give a score to 157...Ba1, instead of just silently switching to 157...Ba3.

ernest
Posts: 247
Joined: Thu Sep 02, 2010 10:33 am

Re: Why did Rybka lose?

Post by ernest » Wed Nov 03, 2010 6:34 pm

hyatt wrote:0.00 is not "bad". It is "draw". Post was about "losing".
Come on Bob, you're getting picky... :)

I just wanted to say that it takes "some time" for Rybka to prefer 157...Ba3 at (0.00),
which means that 157...Ba1 is then evaluated at "worse than (0.00)"

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