Author: Olaf Jenkner
Date: 00:55:29 05/30/02
Go up one level in this thread
On May 30, 2002 at 00:37:14, Robert Hyatt wrote: Can you please answer my second question below? Thanks in advance. >On May 29, 2002 at 18:25:05, Olaf Jenkner wrote: > >>I noticed a big difference between Crafty 18.13 and 18.14 in a >>special position and don't understand what happened. >>Maybe you can explain it. >> >>See this position: >> >>[D]3B4/1r1kp3/r2p1p2/b1pPP1p1/1pP2PPp/pP5P/P2K4/8 w - - 0 1 >> >>After 1.e6+ K:d8 2.f5+ it is a draw. >> >>Version 18.13 finds the move after 35 min at depth 16 >> and gives the evaluation -12.40 >>Version 18.14 finds the move after 150 min at depth 17 gives >> and gives the evaluation -12.34 >> >>xxxxxxxxxxxxxxxxxxx Little Question xxxxxxxxxxxxxxxxxxxxx >>What has been changed in version 18.14 to cause this difference? >>In main.c I didn't find a clue. > >There were minor evaluation changes. Any evaluation change can cause >the time for an odd position to change significantly, even though the >scoring change doesn't affect the final score or best move. > >alpha/beta is a strange animal. > >>xxxxxxxxxxxxxxxxxxx Little Question xxxxxxxxxxxxxxxxxxxxx >> >> >>Here is the output of Crafty 18.13: >> >>12 16.41 -9.97 1. exf6 exf6 2. Bxf6 gxf4 3. Bg5 Rb8 >> 4. Bxf4 Re8 5. Kd3 Re1 6. g5 Ra1 >> 7. Bxd6 Rxd6 >>12-> 17.18 -9.97 1. exf6 exf6 2. Bxf6 gxf4 3. Bg5 Rb8 >> 4. Bxf4 Re8 5. Kd3 Re1 6. g5 Ra1 >> 7. Bxd6 Rxd6 >>13 17.89 -- 1. exf6 >>13 39.90 -10.45 1. exf6 exf6 2. Bxf6 gxf4 3. Bxh4 Rb8 >> 4. Bg5 f3 5. Ke3 Rf8 6. Kf2 Raa8 >> 7.Bh6 Rf6 >>13-> 43.18 -10.45 1. exf6 exf6 2. Bxf6 gxf4 3. Bxh4 Rb8 >> 4. Bg5 f3 5. Ke3 Rf8 6. Kf2 Raa8 >> 7.Bh6 Rf6 >>14 46.61 -- 1. exf6 >>14 2:05 -11.36 1. exf6 Ke8 2. Bxe7 gxf4 3. Kd1 Rxe7 >> 4. fxe7 Ra7 5. g5 Rxe7 6. g6 f3 >> 7. g7 Rxg7 8. Ke1 Rg2 >>14-> 3:15 -11.36 1. exf6 Ke8 2. Bxe7 gxf4 3. Kd1 Rxe7 >> 4. fxe7 Ra7 5. g5 Rxe7 6. g6 f3 >> 7.g7 Rxg7 8. Ke1 Rg2 >>15 3:25 -- 1. exf6 >>15 7:35 -12.28 1. exf6 Ke8 2. f7+ Kxf7 3. Bxa5 Rxa5 >> 4. fxg5 e5 5. dxe6+ Kg6 6. Kd1 Re7 >> 7. Ke2 Rxe6+ 8. Kf2 Ra8 9. Kf1 Rf8+ >> 10. Kg1 Kxg5 >>15-> 8:49 -12.28 1. exf6 Ke8 2. f7+ Kxf7 3. Bxa5 Rxa5 >> 4. fxg5 e5 5. dxe6+ Kg6 6. Kd1 Re7 >> 7. Ke2 Rxe6+ 8. Kf2 Ra8 9. Kf1 Rf8+ >> 10. Kg1 Kxg5 >>16 9:01 -- 1. exf6 >>16 21:25 -12.84 1. exf6 Ke8 2. f7+ Kxf7 3. f5 Bxd8 >> 4. Ke2 Kf6 5. Kf2 Ke5 6. Ke3 Bb6 >> 7. Ke2 Kd4 8. Kd2 Ra5 9. Ke2 >>16 34:43 -12.40 1. e6+ Kxd8 2. f5 Rb8 3. Kc1 Raa8 >> 4. Kd2 Kc7 5. Kc1 Bb6 6. Kd2 Rb7 >> 7. Kc1 Re8 8. Kd2 Rd8 9. Ke3 >>16-> 35:03 -12.40 1. e6+ Kxd8 2. f5 Rb8 3. Kc1 Raa8 >> 4. Kd2 Kc7 5. Kc1 Bb6 6. Kd2 Rb7 >> 7. Kc1 Re8 8. Kd2 Rd8 9. Ke3 >>17 38:02 -12.42 1. e6+ Kxd8 2. f5 Rb8 3. Kc1 Kc7 >> 4. Kd2 Bb6 5. Kc1 Ra5 6. Kd2 Rh8 >> 7. Kd3 Rh6 8. Ke4 Kd8 9. Ke3 Kc7 >>17-> 42:28 -12.42 1. e6+ Kxd8 2. f5 Rb8 3. Kc1 Kc7 >> 4. Kd2 Bb6 5. Kc1 Ra5 6. Kd2 Rh8 >> 7. Kd3 Rh6 8. Ke4 Kd8 9. Ke3 Kc7 >> >> >>Here is the output of Crafty 18.14: >> >>12 21.08 -9.94 1. exf6 exf6 2. Bxf6 gxf4 3. Bg5 Rb8 >> 4. Bxf4 Re8 5. g5 Ke7 6. Ke3 Kf7+ >> 7. Kf3 Kg6 >>12-> 21.92 -9.94 1. exf6 exf6 2. Bxf6 gxf4 3. Bg5 Rb8 >> 4. Bxf4 Re8 5. g5 Ke7 6. Ke3 Kf7+ >> 7. Kf3 Kg6 >>13 22.67 -- 1. exf6 >>13 1:03 -10.16 1. exf6 exf6 2. Bxf6 gxf4 3. Bg5 Rb8 >> 4. Bxf4 Rf8 5. Ke3 Raa8 6. g5 Rae8+ >> 7. Kf3 Rg8 8. Kg4 >>13-> 1:06 -10.16 1. exf6 exf6 2. Bxf6 gxf4 3. Bg5 Rb8 >> 4. Bxf4 Rf8 5. Ke3 Raa8 6. g5 Rae8+ >> 7. Kf3 Rg8 8. Kg4 >>14 1:07 -- 1. exf6 >>14 3:06 -11.36 1. exf6 Ke8 2. Bxe7 gxf4 3. Kd1 Rxe7 >> 4. fxe7 Ra7 5. g5 Rxe7 6. g6 f3 >> 7. g7 Rxg7 8. Ke1 Rg2 >>14-> 4:09 -11.36 1. exf6 Ke8 2. Bxe7 gxf4 3. Kd1 Rxe7 >> 4. fxe7 Ra7 5. g5 Rxe7 6. g6 f3 >> 7.g7 Rxg7 8. Ke1 Rg2 >>15 4:18 -- 1. exf6 >>15 11:19 -12.17 1. exf6 Ke8 2. f7+ Kxf7 3. Bxa5 gxf4 >> 4. Bd8 Kf6 5. Ke2 Ra8 6. Kf3 Kg5 >> 7. Bxe7+ Rxe7 8. Kf2 Re3 9. Kg2 >>15-> 12:51 -12.17 1. exf6 Ke8 2. f7+ Kxf7 3. Bxa5 gxf4 >> 4. Bd8 Kf6 5. Ke2 Ra8 6. Kf3 Kg5 >> 7. Bxe7+ Rxe7 8. Kf2 Re3 9. Kg2 >>16 30:07 -12.37 1. exf6 Ke8 2. f7+ Kxf7 3. Bxa5 gxf4 >> 4. Bd8 Ra8 5. Ke2 Rxd8 6. Kf3 e5 >> 7. dxe6+ Kxe6 8. Kxf4 Rf7+ 9. Ke3 d5 >> 10. cxd5+ Kxd5 11. g5 c4 >>16-> 34:40 -12.37 1. exf6 Ke8 2. f7+ Kxf7 3. Bxa5 gxf4 >> 4. Bd8 Ra8 5. Ke2 Rxd8 6. Kf3 e5 >> 7.dxe6+Kxe6 8. Kxf4 Rf7+ 9. Ke3 d5 >> 10. cxd5+ Kxd5 11. g5 c4 >>17 35:43 -- 1. exf6 >>17 108:54 -12.94 1. exf6 Ke8 2. f5 Bxd8 3. f7+ Kxf7 >> 4. Ke1 Kf6 5. Kd2 Rb8 6. Ke3 Ke5 >> 7.Kf3 Kd4 <HT> >>17 150:54 -12.34 1. e6+ Kxd8 2. f5 Ra8 3. Kd3 Rc8 >> 4.Kd2 Bb6 5. Ke3 Ke8 6. Ke4 Rbc7 >> 7. Kf3 Rd8 8. Ke4 Kf8 9. Ke3 Kg7 >>17-> 150:59 -12.34 1. e6+ Kxd8 2. f5 Ra8 3. Kd3 Rc8 >> 4. Kd2 Bb6 5. Ke3 Ke8 6. Ke4 Rbc7 >> 7. Kf3 Rd8 8. Ke4 Kf8 9. Ke3 Kg7 >>18 164:52 -12.35 1. e6+ Kxd8 2. f5 Ra8 3. Kd3 Kc7 >> 4. Ke3 Rba7 5. Ke4 Bb6 6. Kd3 Ra5 >> 7. Ke2 Rh8 8. Kd3 Rh6 9. Ke4 Kb7 10. Ke3 >>18-> 180:54 -12.35 1. e6+ Kxd8 2. f5 Ra8 3. Kd3 Kc7 >> 4. Ke3 Rba7 5. Ke4 Bb6 6. Kd3 Ra5 >> 7. Ke2 Rh8 8. Kd3 Rh6 9. Ke4 Kb7 10. Ke3 >> >> >>Before Crafty finds 1.e6+ it considers 1.exf6 Ke8. >>I tried to find out why Crafty 18.14 needs one ply more. >> >>See the diagram: >> >>[D]3Bk3/1r2p3/r2p1P2/b1pP2p1/1pP2PPp/pP5P/P2K4/8 w - - 0 1 >> >>Crafty 18.13: >> >>12 3.21 -- 1. Bxe7 >>12 6.48 -11.36 1. Bxe7 gxf4 2. g5 Rxe7 3. fxe7 Ra7 >> 4. g6 Rxe7 5. Kd1 f3 6. g7 Rxg7 >> 7. Ke1 Rg2 >>12-> 15.39 -11.36 1. Bxe7 gxf4 2. g5 Rxe7 3. fxe7 Ra7 >> 4. g6 Rxe7 5. Kd1 f3 6. g7 Rxg7 >> 7. Ke1 Rg2 >>13 16.30 -- 1. Bxe7 >>13 24.18 -11.98 1. Bxe7 gxf4 2. g5 Rxe7 3. fxe7 Ra7 >> 4. Ke2 Rxe7+ 5. Kf2 Re3 6. g6 Rxh3 >> 7. g7 Rg3 8. g8=Q+ Rxg8 9. Kf3 >>13-> 37.73 -11.98 1. Bxe7 gxf4 2. g5 Rxe7 3. fxe7 Ra7 >> 4. Ke2 Rxe7+ 5. Kf2 Re3 6. g6 Rxh3 >> 7. g7 Rg3 8. g8=Q+ Rxg8 9. Kf3 >>14 38.74 -- 1. Bxe7 >>14 2:08 -13.17 1. Bxe7 gxf4 2. Bxd6 Rxd6 3. g5 Rxd5+ >> 4. cxd5 c4 5. Kc2 c3 6. Kd3 Bd8 >> 7. d6 Bxf6 8. gxf6 >>14 6:11 -12.97 1. f7+ Kxf7 2. f5 Kf6 3. Ke2 Ke5 >> 4. Kd2 Ra8 5. Ke3 Rxd8 6. Kf3 Kd4 >> 7. Ke2 Rbd7 <HT> >>14 8:13 -12.94 1. f5 Bxd8 2. f7+ Kxf7 3. Ke2 Kf6 >> 4. Kf2 Ke5 5. Ke3 Ba5 <HT> >>14-> 8:15 -12.94 1. f5 Bxd8 2. f7+ Kxf7 3. Ke2 Kf6 >> 4. Kf2 Ke5 5. Ke3 Ba5 6. Kd3 <HT> >>15 9:35 -12.94 1. f5 Bxd8 2. f7+ Kxf7 3. Ke2 Kf6 >> 4. Kf2 Ke5 5. Ke3 Ba5 6. Kf3 Kd4 >> 7. Ke2 Rb8 8. Kd2 Rf8 >>15-> 10:03 -12.94 1. f5 Bxd8 2. f7+ Kxf7 3. Ke2 Kf6 >> 4. Kf2 Ke5 5. Ke3 Ba5 6. Kf3 Kd4 >> 7. Ke2 Rb8 8. Kd2 Rf8 >>16 16:04 -13.09 1. f5 Bxd8 2. f7+ Kxf7 3. Ke2 Kf6 >> 4. Kf2 Ke5 5. Ke3 Ra8 6. Ke2 Kf4 >> 7. Kf2 Bb6 8. Kg2 Ke3 9. Kh2 >>16-> 17:47 -13.09 1. f5 Bxd8 2. f7+ Kxf7 3. Ke2 Kf6 >> 4. Kf2 Ke5 5. Ke3 Ra8 6. Ke2 Kf4 >> 7. Kf2 Bb6 8. Kg2 Ke3 9. Kh2 >> >>After 2 minutes (14 plies) the evaluation drops under the >>limit of -12.40 and stays below it. 14 plies sounds logical >>because one move (2 plies) before the solution was found at >>ply 16. >> >>But now look at the output of Crafty 18.14. It is the reason >>why I wrote this posting: >> >>12 3.76 -- 1. Bxe7 >>12 8.10 -11.36 1. Bxe7 gxf4 2. g5 Rxe7 3. fxe7 Ra7 >> 4. g6 Rxe7 5. Kd1 f3 6. g7 Rxg7 >> 7. Ke1 Rg2 >>12-> 19.26 -11.36 1. Bxe7 gxf4 2. g5 Rxe7 3. fxe7 Ra7 >> 4. g6 Rxe7 5. Kd1 f3 6. g7 Rxg7 >> 7. Ke1 Rg2 >>13 20.32 -- 1. Bxe7 >>13 30.06 -11.98 1. Bxe7 gxf4 2. g5 Rxe7 3. fxe7 Ra7 >> 4. Ke2 Rxe7+ 5. Kf2 Re3 6. g6 Rxh3 >> 7. g7 Rg3 8. g8=Q+ Rxg8 9. Kf3 >>13-> 40.30 -11.98 1. Bxe7 gxf4 2. g5 Rxe7 3. fxe7 Ra7 >> 4. Ke2 Rxe7+ 5. Kf2 Re3 6. g6 Rxh3 >> 7. g7 Rg3 8. g8=Q+ Rxg8 9. Kf3 >>14 41.27 -- 1. Bxe7 >>14 2:26 -13.17 1. Bxe7 gxf4 2. Bxd6 Rxd6 3. g5 Rxd5+ >> 4. cxd5 c4 5. Kc2 c3 6. Kd3 Bd8 >> 7. d6 Bxf6 8. gxf6 >>14 5:36 -12.99 1. f7+ Kxf7 2. f5 Kf6 3. Kd3 Ke5 >> 4. Ke2 Bxd8 5. Ke3 Ra8 6. Kf3 Kd4 >> 7. Ke2 Ke4 8. Ke1 <HT> >>14 8:18 -12.93 1. f5 Bxd8 2. f7+ Kxf7 3. Kd3 Ra8 >> 4. Kd2 Kf6 <HT> >>14-> 8:18 -12.93 1. f5 Bxd8 2. f7+ Kxf7 3. Kd3 Ra8 >> 4. Kd2 Kf6 <HT> >>15 9:58 -12.99 1. f5 Bxd8 2. f7+ Kxf7 3. Kd3 Kf6 >> 4. Ke4 Raa7 5. Kd3 Ke5 6. Ke2 Ra6 >> 7. Ke3 Ra8 <HT> >>15-> 10:33 -12.99 1. f5 Bxd8 2. f7+ Kxf7 3. Kd3 Kf6 >> 4. Ke4 Raa7 5. Kd3 Ke5 6. Ke2 Ra6 >> 7. Ke3 Ra8 <HT> >>16 10:38 -- 1. f5 >>16 54:16 -13.09 1. f5 Bxd8 2. f7+ Kxf7 3. Kd3 Kf6 >> 4. Kd2 Ke5 5. Ke3 Ra8 6. Ke2 Kf4 >> 7. Kf2 Bb6 8. Kg2 Ke3 9. Kh2 >>16-> 56:35 -13.09 1. f5 Bxd8 2. f7+ Kxf7 3. Kd3 Kf6 >> 4. Kd2 Ke5 5. Ke3 Ra8 6. Ke2 Kf4 >> 7. Kf2 Bb6 8. Kg2 Ke3 9. Kh2 >>17 56:42 -- 1. f5 >> >>After 2.5 minutes (14 plies) the evaluation drops under the >>limit of -12.34 and stays below it. >> >>XXXXXXXXXXXXXXXXXXX BIG QUESTION XXXXXXXXXXXXXXXXXXXXXXXX >>Why do we have such a big difference in the first position? >>The difference in the second position is vey small. >>XXXXXXXXXXXXXXXXXXX BIG QUESTION XXXXXXXXXXXXXXXXXXXXXXXX >> >> >>Crafty was running on a 333 MHz PII. >> >>Olaf Jenkner
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