Author: Chessfun
Date: 08:32:05 04/15/04
Go up one level in this thread
On April 15, 2004 at 10:30:19, Stephen Ham wrote: >On April 14, 2004 at 20:46:20, Sam Lloyd wrote: > >>On April 14, 2004 at 11:12:08, Stephen Ham wrote: >> >>>Hi Terry, >>> >>>I agree with you and am glad that 13 a3! interests you as well. >>> >>>As you know, I'm a correspondnece chess player with a technical style of play >>>(tactics aren't my strength - especially against machines!). So I've had fun >>>testing engines to see if any of them will select my purely human moves. So far, >>>there's been very little acceptance of my positional/technical move tests by the >>>engines. The closest correlation seems to be with Rebel 12. In one of my tests, >>>it was the only engine to select the move that I played. When I fed my move into >>>the other engines that didn't select my move, their evaluations eventually rose >>>to a favorable figure. So it's clear that engines in general won't find the >>>"positional" moves that I think are best. But when forced to play the move, they >>>eventually learn to like the resulting positions, although the evaluation may >>>not be as high as the original PV for that engine. >>> >>>So I think it would be fun for you and other engine experts to test 13 a3! to >>>see if any engine selects it. Since the justifications behind 13 a3! are deep >>>(they certainly are for humans), you may need to allow 24-hours or so for the >>>test. >>> >>>Thanks again for mentioning this game, Terry. It is indseed rich in test >>>positions, both tactically and of a positional/technical nature. I'll try to >>>Rebel 12 on this position and will report what it selects. >>> >>>Stephen >>> >>Rebel 12 finds 13. a3 instantly, and stays with it. >> >>Hiarcs 9 takes a little longer, but as I suspected found 13. a3 and stays with >>it as well. >> >>My hardware is prehistoric by todays standards. P-III 500 128MB RAM with 64MB >>for HTs. >> >>Hiarcs 9 - McCracken,T >>[D]r1bq1rk1/3nbppp/2n1p3/2ppP3/pp3B1P/3P1NP1/PPP2PB1/R2QRNK1 w - - 0 1 >> >>Analysis by Hiarcs 9: >> >>13.Qd2 a3 >> ³ (-0.44) Depth: 1/2 00:00:00 >>13.Qd2 Bb7 14.c3 >> ³ (-0.63) Depth: 2/6 00:00:00 >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 2/6 00:00:00 >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 2/6 00:00:00 >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 3/6 00:00:00 >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 4/6 00:00:00 >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 5/6 00:00:00 >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 6/6 00:00:00 >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 7/8 00:00:00 1kN >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 8/8 00:00:00 1kN >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra8 17.Bb2 Bb7 >> ³ (-0.44) Depth: 9/12 00:00:00 4kN >>13.h5 f6 14.exf6 Rxf6 15.Qe2 a3 16.b3 Nb6 17.Ne5 Nxe5 18.Bxe5 >> ³ (-0.43) Depth: 10/26 00:00:58 2162kN >>13.h5 a3 14.bxa3 Rxa3 15.h6 g6 16.Bc1 Ra5 17.Bb2 Bg5 18.Nxg5 Qxg5 19.c4 >> ³ (-0.56) Depth: 11/27 00:02:24 5363kN >>13.a3 Bb7 >> ³ (-0.55) Depth: 11/27 00:03:13 7211kN >>13.a3 bxa3 14.bxa3 Ba6 15.h5 c4 16.h6 g5 17.Nxg5 Bxg5 18.Qg4 Ncxe5 19.Qxg5+ >> ³ (-0.46) Depth: 11/28 00:04:38 10347kN >>13.a3 bxa3 14.bxa3 Rb8 15.c4 Nb6 16.Ne3 Na5 17.Rb1 Nb3 18.Nd2 dxc4 19.Ndxc4 Ba6 >> ³ (-0.32) Depth: 12/30 00:12:30 28289kN >>13.a3 bxa3 14.bxa3 Re8 15.c4 Nb6 16.Ne3 Rb8 17.Rb1 >> ³ (-0.29) Depth: 13/37 00:37:12 83484kN >> >>(McCracken, None 14.04.2004) >> >>Terry > >Thanks, Terry and Richard, for running those tests. I confess that I'm amazed by >the results. Both you, with Rebel and Hiarcs, and Richard's Baron found 13 a3. I >must admit that if I had to bet money, I would have bet against any engine, >other than possibly Rebel, in finding 13 a3. And I would have bet that Rebel >would require overnight analysis to find it. Again, the results are astounding. > >What's interesting too is that these engines, while finding the best move, >probably don't comprehend the position very well, since they all seem to give a >very slight edge to Black. Instead, most humans, especially after seeing the >motifs in the Fischer game and similar motifs in the Closed Sicilian, would >favor White with a clear advantage. > >Perhaps this is yet another example of engines finding the correct move, but >their evaluations are wrong. I see this with Shredder all the time. Then it should be no surprise to you that Shredder 8 also finds the move: XP 2600+ 64 Mb New game r1bq1rk1/3nbppp/2n1p3/2ppP3/pp3B1P/3P1NP1/PPP2PB1/R2QRNK1 w - - 0 1 Analysis by Shredder 8: 1.a3 Bb7 2.axb4 cxb4 3.d4 a3 4.Ra2 Ba6 5.Qd2 Qb6 ³ (-0.36) Depth: 9/24 00:00:00 200kN 1.a3 Qb6 2.axb4 cxb4 3.Be3 Qa5 4.d4 Ba6 5.Bg5 Rac8 6.c4 bxc3 7.Bxe7 Nxe7 8.Rxa4 ³ (-0.33) Depth: 10/27 00:00:01 504kN 1.a3 Bb7 2.axb4 cxb4 3.h5 a3 4.h6 axb2 5.Rxa8 Qxa8 6.hxg7 Kxg7 ³ (-0.28) Depth: 11/29 00:00:05 1530kN 1.a3 bxa3 2.bxa3 Rb8 3.c4 Rb3 4.N3d2 Rxd3 5.Qxa4 Bb7 6.cxd5 Qa8 7.Qxa8 ³ (-0.28) Depth: 12/32 00:00:09 2895kN 1.a3 Qb6 2.h5 h6 3.c4 Qa5 4.cxd5 exd5 5.e6 b3 6.exd7 Qc3 7.bxc3 ³ (-0.27) Depth: 13/34 00:00:19 6142kN 1.a3 Bb7 2.h5 h6 3.c3 Qa5 4.cxb4 Qb6 5.bxc5 Bxc5 6.Qc2 Rac8 7.Rac1 Qb5 = (-0.24) Depth: 14/34 00:00:38 11793kN 1.a3 Qb6 2.Qd2 f6 3.exf6 Bxf6 4.c3 e5 5.Be3 d4 6.Bg5 Bb7 7.Bxf6 Rxf6 8.axb4 dxc3 9.bxc5 ³ (-0.28) Depth: 15/37 00:01:12 20540kN 1.a3 Qb6 2.Ne3 Ba6 3.axb4 Qxb4 4.Rb1 Rfb8 5.Qc1 Qa5 6.c4 Nb4 7.Qd2 Qc7 8.cxd5 exd5 = (-0.24) Depth: 16/39 00:02:54 51981kN Sarah.
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