Author: Uri Blass
Date: 07:52:36 06/14/04
Go up one level in this thread
On June 14, 2004 at 09:36:33, Mridul Muralidharan wrote: >On June 14, 2004 at 02:22:40, Uri Blass wrote: > >>On June 14, 2004 at 02:06:17, Uri Blass wrote: >> >>>On June 14, 2004 at 01:25:57, Mridul Muralidharan wrote: >>> >>>>Hi all, >>>> >>>> I have been following the games of my engine and one very painful thing is to >>>>see it fall from +4.x to 0.0 due to a king hunt by opponent. >>>>Some programs like yace , frenzee (atleast in one the games I saw) , etc seem to >>>>identify this correctly and immediately take the eval down to 0.0 - this is not >>>>a search depth thing. >>>>My engine on the other hand needs a few moves to see the inevitability of the >>>>position. >>>>I am sure it might not be always possible to detect a king hunt always with 100% >>>>accuracy , but any general tips , comments to get me started would be great ! >>>> >>>> >>>>Thanks >>>>Mridul >>>> >>>>PS : Here is a game at icc today morning where it happens again from my winboard >>>>saved game : the comments are also present which give an idea of the evals by >>>>both engines. >>>> >>>>For my initial look : >>>> >>>>[D] 6rk/pnp2p1n/1p1p3p/3PpN1q/4P1r1/2P1Q1B1/P1P2PP1/1R2R1K1 b - - 0 24 >>>> >>>>Here , Ng5 gets played since borer does not understand that the position might >>>>lead to a draw ! >>> >>>I do not think that the game moves after Ng5 are forced from black point of >>>view. >>> >>>30...Qh1+ lead to a draw but yace suggests 30...Rg3 with evaluation of advantage >>>for black >>> >>>PostModernist - witchess, ICS rated standard match 2004 >>>[D]7k/pnp2p2/1p1p3p/3Pp3/4P3/2P1QP1q/P1P1R1r1/1R2K3 b - - 0 1 >>> >>>Analysis by Yace Paderborn: >>> >>>30...Rxe2+ 31.Kxe2 >>> ± (0.88) Depth: 1 00:00:00 >>>30...Rh2 31.Rxh2 Qxh2 >>> ± (0.80) Depth: 1 00:00:00 >>>30...h5 31.Rxg2 Qxg2 >>> ± (0.76) Depth: 1 00:00:00 >>>30...Qg3+ 31.Kd2 >>> ² (0.65) Depth: 1 00:00:00 >>>30...Qg3+ 31.Kd2 >>> ² (0.65) Depth: 1 00:00:00 >>>30...Qh1+ 31.Qg1 >>> ² (0.29) Depth: 1 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 >>> -+ (-3.15) Depth: 1 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 >>> -+ (-3.15) Depth: 1 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 >>> -+ (-3.15) Depth: 2 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 >>> -+ (-3.15) Depth: 2 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 >>> -+ (-3.15) Depth: 3 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 >>> -+ (-3.15) Depth: 3 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 >>> -+ (-3.31) Depth: 4 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 >>> -+ (-3.31) Depth: 4 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 35.Qh6+ Ke8 36.Qh8+ >>>Kd7 >>> -+ (-3.57) Depth: 5 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 35.Qh6+ Ke8 36.Qh8+ >>>Kd7 >>> -+ (-3.57) Depth: 5 00:00:00 >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Qxe2 Qxb1 33.Qa6 Nc5 34.Qc8+ Kg7 35.Qxc7 Qxa2 36.Qxd6 >>> -+ (-3.43) Depth: 6/18 00:00:00 41kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Qxe2 Qxb1 33.Qa6 Nc5 34.Qc8+ Kg7 35.Qxc7 Qxa2 36.Qxd6 >>> -+ (-3.43) Depth: 6/19 00:00:00 63kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Qxe2 Qxb1 33.Qa6 Nc5 34.Qc8+ Kg7 35.Qxc7 Qxa2 36.Qxd6 >>> -+ (-3.43) Depth: 7/19 00:00:00 92kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Qxe2 Qxb1 33.Qa6 Nc5 34.Qc8+ Kg7 35.Qxc7 Qxa2 36.Qxd6 >>> -+ (-3.43) Depth: 7/26 00:00:00 188kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Qxe2 Qxb1 33.Qa6 Qg1 34.Qxb7 Qf2+ 35.Kc1 Qxf3 >>> -+ (-3.03) Depth: 8/26 00:00:00 237kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 35.Qh6+ Ke8 36.Qh8+ >>>Kd7 37.Qh3+ Ke7 38.Qh4+ f6 39.Qh7+ Kd8 40.Qg8+ Kd7 41.Qe6+ Kd8 42.Qxf6+ Kd7 >>>43.Qf7+ Kc8 44.Qe6+ Kd8 >>> -+ (-2.65) Depth: 8/26 00:00:01 304kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 35.Qh6+ Ke8 36.Qh8+ >>>Kd7 37.Qh3+ Ke7 38.Qh4+ f6 39.Qh7+ Kd8 40.Qg8+ Kd7 41.Qe6+ Kd8 42.Qxf6+ Kd7 >>>43.Qf7+ Kc8 44.Qe6+ Kd8 >>> -+ (-2.65) Depth: 8/30 00:00:01 623kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 35.Qh6+ Ke8 36.Qh8+ >>>Kd7 37.Qh3+ Kd8 38.Qh4+ Kc8 39.Qg4+ Kb8 40.Qg8+ Nd8 41.Qxd8+ Kb7 >>> -+ (-2.25) Depth: 9/30 00:00:02 679kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 35.Qh6+ Ke8 36.Qh8+ >>>Kd7 37.Qh3+ Kd8 38.Qh4+ Kc8 39.Qg4+ Kb8 40.Qg8+ Nd8 41.Qxd8+ Kb7 >>> µ (-1.25) Depth: 9/31 00:00:02 707kN >>>30...Qh1+ 31.Kd2 Rxe2+ 32.Kxe2 Qxb1 33.Qxh6+ Kg8 34.Qg5+ Kf8 35.Qh6+ Ke8 36.Qh8+ >>>Kd7 37.Qh3+ Kd8 38.Qh8+ Ke7 39.Qh4+ Kd7 40.Qh3+ Kd8 41.Qh8+ Ke7 42.Qh4+ Kd7 >>>43.Qh3+ >>> = (0.00) Depth: 9/32 00:00:02 761kN >>>30...Rg3 31.Kd2 Rxf3 32.Qxh6+ Qxh6+ 33.Re3 >>> = (-0.01) Depth: 9/32 00:00:03 1451kN >>>30...Rg3 31.Kd2 Na5 32.Qd3 Rxf3 33.Qb5 Rxc3 34.Qe8+ Kg7 35.Rg1+ Rg3 36.Re3 >>> ³ (-0.53) Depth: 9/32 00:00:05 2271kN >>>30...Rg3 31.Kd2 Na5 32.Qd3 Rxf3 33.Qb5 Rxc3 34.Qe8+ Kg7 35.Rg1+ Rg3 36.Re3 >>> ³ (-0.53) Depth: 9/32 00:00:07 3085kN >>>30...Rg3 31.Kd2 Rxf3 32.Qg1 Qh4 33.Qh2 Qg5+ 34.Ke1 Nc5 35.c4 Qg3+ 36.Qxg3 Rxg3 >>>37.Rb5 >>> ³ (-0.52) Depth: 10/32 00:00:11 4393kN >>>30...Rg3 31.Kd2 Rxf3 32.Qg1 Qh4 33.Qh2 Qg5+ 34.Ke1 Nc5 35.c4 Qg3+ 36.Qxg3 Rxg3 >>>37.Rb5 >>> ³ (-0.52) Depth: 10/33 00:00:17 7304kN >>>30...Rg3 31.Kd2 Na5 32.Qd3 Rxf3 33.Qa6 Rxc3 >>> ³ (-0.56) Depth: 11/33 00:00:27 11504kN >>>30...Rg3 31.Kd2 Na5 32.Qd3 Rxf3 33.Qa6 Rxc3 >>> ³ (-0.56) Depth: 11/39 00:00:45 19193kN >>>30...Rg3 31.Kd2 Rxf3 32.Qg1 Nc5 33.Rbe1 Rg3 34.Qh1 Qxh1 35.Rxh1 Kg7 36.Rh5 a5 >>> ³ (-0.63) Depth: 12/39 00:01:10 29481kN >>> >>>(Blass, Tel-Aviv 14.06.2004) >>> >>>Uri >> >>I can add that 29...Nc5 is also better and it is certainly a search problem. >> >>Uri > >There are n number of better moves IF you know that Qh1+ is a draw. I think that it is a search problem and programs like yace that do a lot of chess extensions solve it by search. Based on my experience with Yace I think that king safety is one of it's weakness so it probably solves it by search and not by evaluation. Movei is slower than yace but it also solve it by search and not by evaluation after Qh1+ fail low at depth 10 from +2.48 score to 0.96 pawn advantage. 9 248 194 429491 h3h1 e1d2 g2e2 d2e2 h1b1 e3h6 h8g8 h6g5 g8f8 g5h6 f8e8 h6h8 e8 d7 h8h3 d7e7 h3h4 f7f6 h4h7 e7f8 h7h8 f8f7 h8h7 f7e8 h7g8 e8d7 g8e6 d7d8 e6f6 9 248 401 899159 h3h1 e1d2 g2e2 d2e2 h1b1 e3h6 h8g8 h6g5 g8f8 g5h6 f8e8 h6h8 e8 d7 h8h3 d7e7 h3h4 f7f6 h4h7 e7f8 h7h8 f8f7 h8h7 f7e8 h7g8 e8d7 g8e6 d7d8 e6f6 10 96 560 1274758 h3h1 e1d2 g2e2 d2e2 h1b1 e3h6 h8g8 h6g5 g8f8 g5h6 f8e8 h6h8 e 8d7 h8h3 d7d8 h3h4 d8c8 h4g4 c8b8 g4g8 b7d8 g8d8 b8b7 e2e3 b1a2 10 97 1344 2921379 g2g3 10 126 1658 3570023 g2g3 10 145 2375 5046840 g2g3 e1d2 b7a5 b1b4 c7c5 b4a4 g3f3 e3g1 f3c3 d2d1 10 145 2681 5716954 g2g3 e1d2 b7a5 b1b4 c7c5 b4a4 g3f3 e3g1 f3c3 d2d1 11 98 3056 6484651 g2g3 e1d2 b7a5 b1b4 c7c5 b4a4 g3f3 e3g1 f3g3 g1h2 g3c3 h2h3 c3h3 11 98 5220 9565624 g2g3 e1d2 b7a5 b1b4 c7c5 b4a4 g3f3 e3g1 f3g3 g1h2 g3c3 h2h3 c3h3 12 115 6044 11204193 g2g3 e1d2 g3f3 e3g1 h3h4 e2e3 f3f2 d2c1 b7c5 c1b2 f2f4 e3g 3 c5a4 b2a1 f4e4 g3g8 h8h7 12 115 8890 17113757 g2g3 e1d2 g3f3 e3g1 h3h4 e2e3 f3f2 d2c1 b7c5 c1b2 f2f4 e3g 3 c5a4 b2a1 f4e4 g3g8 h8h7 13 103 10564 20487105 g2g3 e1d2 g3f3 e3g1 h3h4 e2e3 f3e3 g1e3 b7c5 b1e1 b6b5 e3 e2 h6h5 Uri
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