Author: Mridul Muralidharan
Date: 06:36:33 06/14/04
Go up one level in this thread
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. Without that (like knight at f7 instead of pawn , etc) , this is a win : quiet simple. You have to "know" that the position is a draw. After playing Qh1 , there is no point in seeing a draw - it is too late. You should see it before - and I dont think you will search deep enough in tourny time to see it from Ng5 stage. Your eval has to resolve this ..... I am checking google "agressively" :) Maybe that will give some suggestions ... Mridul
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.