Author: Ernst Walet
Date: 00:01:15 05/13/00
Go up one level in this thread
On May 12, 2000 at 16:21:01, blass uri wrote: >[D]1r3nk1/3rb1p1/p2p1pP1/1p2p3/Pnq1P1R1/2N1B3/1PPR3P/2NQ3K w - - 0 1 > >This position is from the ssdf games(Junior5-Junior6). >The evaluation was close to equality and suddenly Junior5 failed high and found >more than 1 pawn advantage for white. > >I post this position to demonstrate the fact that tactics is not only >sacrifices. > >Unfortunately tactical test positions are usually sacrifices. > >I am also not sure if there is only one good move for white. >White played in the game Rg2. >This is a good move with the idea to give mate by Rh4 and Qh5 but I am not sure >if this is the only good move and it is possible that axb5 and after it Rg2 also >give the same result(I did not check it) > >The point is not to find Rg2 but to find a significant change in the evaluation. > >How much do programs need to fail high? > >I think it is a good idea to generate a tactical test suite based on positions >from practical games and not based on finding sacrifices. > >In order to do it we need to analyze many games and find cases when there is a >significant change in the evaluation. > > >Uri This is what Fritz6a does on my PIII-450 with 128MB hash. It needs 5:34 to fail high and 10:32 to resolve it. New position 1r3nk1/3rb1p1/p2p1pP1/1p2p3/Pnq1P1R1/2N1B3/1PPR3P/2NQ3K w - - 0 1 Analysis by Fritz 6: 1.axb5 axb5 2.Kg2 Ra8 3.Nd5 Nxd5 4.Rxd5 ² (0.53) Depth: 4/13 00:00:00 2kN 1.axb5 axb5 2.Kg2 Ra8 3.Nd5 Nxd5 4.Rxd5 ² (0.53) Depth: 4/13 00:00:00 2kN 1.axb5 axb5 2.Kg2 Ra8 3.Nd5 Nxd5 4.Rxd5 ² (0.53) Depth: 4/13 00:00:00 2kN 1.axb5 axb5 2.Kg2 Ra8 3.Nd5 Nxd5 4.Rxd5 ² (0.53) Depth: 4/13 00:00:00 2kN 1.axb5 axb5 2.Kg2 Ra8 3.Nd5 Nxd5 4.Rxd5 ² (0.53) Depth: 4/13 00:00:00 2kN 1.axb5 axb5 2.Kg2 Ra8 3.Nd5 Nxd5 4.Rxd5 ² (0.53) Depth: 4/13 00:00:00 2kN 1.axb5 axb5 2.Kg2 Ra8 3.Nd5 Nxd5 4.Rxd5 ² (0.53) Depth: 4/13 00:00:00 2kN 1.axb5 axb5 2.Nd5 Nxd5 3.exd5 e4 4.Rf2 ² (0.59) Depth: 5/20 00:00:00 14kN 1.axb5 axb5 2.Kg2 Ne6 3.Nb3 Ra8 4.Nd5 Nxd5 5.Rxd5 ² (0.53) Depth: 6/18 00:00:00 32kN 1.axb5 axb5 2.Nd5 Nxd5 3.exd5 Qc7 4.Rf2 Re8 5.Qf3 ² (0.53) Depth: 7/23 00:00:00 118kN 1.axb5 axb5 2.Nd5 Nxd5 3.exd5 Qc7 4.Rf2 Ra8 5.Qe2 Ra5 ² (0.56) Depth: 8/24 00:00:01 256kN 1.axb5 axb5 2.Nd3 Bd8 3.Rf2 Ne6 ² (0.59) Depth: 9/27 00:00:03 875kN 1.axb5 axb5 2.Nd3 Bd8 3.Nxb4 Qxb4 4.Qb1 Qc4 5.Nd5 Ra8 ² (0.63) Depth: 10/28 00:00:06 1995kN 1.axb5 axb5 2.Rf2 Bd8 3.Nd3 ² (0.66) Depth: 11/33 00:00:18 5812kN 1.axb5 axb5 2.Nd3 Bd8 3.Nxb4 Qxb4 4.Rd3 Qxb2 5.Rxd6 Rxd6 ² (0.59) Depth: 12/34 00:01:09 22312kN 1.axb5 axb5 2.Nd3 Na2 3.Nd5 f5 4.Nxe7+ Rxe7 5.exf5 Qc6+ ² (0.56) Depth: 13/36 00:03:08 61747kN 1.Rdg2 ² (0.59) Depth: 13/40 00:05:34 111448kN 1.Rdg2 bxa4 2.Rh4 f5 3.Rh3 Nxg6 4.Rxg6 Nxc2 5.Nd3 Nxe3 ± (1.16) Depth: 13/40 00:10:32 210385kN Shredder4 needs more time, 15:23 to fail high and 45:12 to resolve it. (PIII-450, 96+32 MB hash) 6 -> 0:00.96 +0.27 axb5 axb5 Qf3 Nc6 Qf5 Rdd8 Rh4 (77.231) 80.4 7.01 0:02.87 +0.18 axb5 axb5 Qe2 Ne6 Qg2 Nd4 Bxd4 exd4 Nd1 (235.185) 81.8 7.04 0:04.40 +0.19++ Kg1 bxa4 Nxa4 Rdd8 c3 f5 exf5 Nd7 (341.423) 77.5 7.04 0:04.51 +0.19 Kg1 bxa4 Nxa4 Rdb7 Rd4 exd4 Qe2 Qxe2 (351.391) 77.8 7 -> 0:05.97 +0.19 Kg1 bxa4 Nxa4 Rdb7 Rd4 exd4 Qe2 Qxe2 (479.564) 80.3 8.01 0:07.35 +0.15 Kg1 bxa4 Nxa4 Rdb7 c3 Nc6 b3 Qb5 Rd5 (609.705) 82.8 8.02 0:08.41 +0.16++ axb5 axb5 Kg1 Ne6 Qf3 Nd4 Qg2 d5 exd5 Nxd5 Bxd4 Nxc3 bxc3 Rxd4 cxd4 Qxd4+ Rgxd4 (710.877) 84.4 8.02 0:13.82 +0.24 axb5 axb5 Rf2 Rdd8 N1e2 Nc6 Rxf6 Bxf6 Qd5+ Qxd5 (1.189.428) 86.0 8 -> 0:15.62 +0.24 axb5 axb5 Rf2 Rdd8 N1e2 Nc6 Rxf6 Bxf6 Qd5+ Qxd5 (1.367.997) 87.5 9.01 0:31.56 +0.37 axb5 axb5 Nd3 Ra8 Nxb4 Qxb4 Rf2 Qc4 Qf1 Rb7 Qh3 (2.776.481) 87.9 9 -> 0:35.80 +0.37 axb5 axb5 Nd3 Ra8 Nxb4 Qxb4 Rf2 Qc4 Qf1 Rb7 Qh3 (3.180.765) 88.8 10.01 0:48.32 +0.46 axb5 axb5 Nd3 Nxd3 Rxd3 Ra8 Nd5 Bd8 b3 Qc8 Rc3 Bc7 (4.366.475) 90.3 10 -> 0:51.74 +0.46 axb5 axb5 Nd3 Nxd3 Rxd3 Ra8 Nd5 Bd8 b3 Qc8 Rc3 Bc7 (4.696.487) 90.7 11.01 1:41.00 +0.43 axb5 axb5 Nd3 Bd8 Nxb4 Qxb4 Rf2 d5 exd5 Qxb2 Qd3 Rc7 Bd2 (9.258.273) 91.6 11 -> 2:15.00 +0.43 axb5 axb5 Nd3 Bd8 Nxb4 Qxb4 Rf2 d5 exd5 Qxb2 Qd3 Rc7 Bd2 (12.260.349) 90.8 12.01 4:54.92 +0.43 axb5 axb5 Nd3 Bd8 Rf2 Nc6 Nd5 b4 b3 Qb5 Qe1 (26.612.056) 90.2 12.25 15:23.56 +0.44++ Rdg2 bxa4 Rh4 Nc6 (78.451.980) 84.9 12.25 19:21.31 +0.79++ Rdg2 bxa4 Rh4 Nc6 Qh5 Qe6 Nxa4 Nxg6 Qxg6 (98.694.373) 84.9 12.25 45:12.96 +1.26 Rdg2 d5 exd5 Nxd5 Rxc4 Nxe3 Qf3 Nxg2 Rc6 Nf4 (224.712.217) 82.8 12 -> 45:16.26 +1.26 Rdg2 d5 exd5 Nxd5 Rxc4 Nxe3 Qf3 Nxg2 Rc6 Nf4 (224.991.564) 82.8 best move: Rd2-g2 time: 65:13.138 min n/s: 82.486 nodes: 322.781.564 Ernst.
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