Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: A possible DB analysis move

Author: Robert Hyatt

Date: 21:22:28 07/23/02

Go up one level in this thread


On July 23, 2002 at 19:40:59, John Merlino wrote:

>On July 23, 2002 at 19:31:10, John Merlino wrote:
>
>>On July 23, 2002 at 18:32:27, Robert Hyatt wrote:
>>
>>>A few years ago, Komputer Korner had a "correspondence kup" match with Crafty,
>>>chessmaster and some other programs, playing a correspondence tournament.  In
>>>that match, Crafty found a wild sacrifice to play against Chessmaster, I think
>>>it was Nf6.  After searching for 24 hours or whatever the time limit was, Crafty
>>>saw a draw score.  And it saw a draw score for the next couple of moves.
>>>
>>>Right after Crafty played that move, Hsu sent me an email saying "brilliant
>>>move".  I told him Crafty only saw a draw.  He said "let it keep searching...
>>>DB Jr saw +2.5 very quickly."  Sure enough, a few moves later Crafty realized
>>>it was not just drawing, it was winning easily.
>>>
>>>I will try to find the game.  If anybody has it, perhaps _that_ position will
>>>be a good one to see how long it takes today's programs to find the move and
>>>find it is winning, compared to DB1 back in 1996...
>>>
>>>I will see what I can find...
>>>
>>>I think the event was called "the komputer kup korrespondence tournament" or
>>>something similar...
>>
>>Assuming Pierre's position is correct, Chessmaster 9000, on a PIII-600, finds
>>Nf6+ in 1:16, giving it a drawing score. After 3:15, the score is positive, but
>>nowhere near "winning".
>>
>>Time	Depth	Score	Positions	Moves
>>0:00	1/4	-0.41	11390		19.Bh6 Re6 20.Bg5 Nd4 21.Qd3
>>0:00	1/5	-0.64	37849		19.Bh6 Re6 20.Be3 Nd4 21.Bxd4 exd4
>>0:01	1/5	-0.46	67804		19.Bg3 Nd4 20.Qe4 Qb8 21.Rac1 Bf5
>>0:02	1/6	-0.42	111216		19.Bg3 Nd4 20.Qh5 Be6 21.Bxe5 Bxd5
>>					22.Bxd4
>>0:04	1/6	-0.37	203824		19.Bh6 Re6 20.Be3 Nd4 21.Bxd4 Bxd4
>>0:06	1/7	-0.56	341780		19.Bh6 Re6 20.Be3 Nd4 21.Bxd4 exd4
>>					22.Rac1 Re5
>>0:13	1/7	-0.52	692298		19.Re1 Kh8 20.Nc3 Qc7 21.Bxe5 Rxe5
>>					22.Rxe5 Qxe5 23.Qxc6
>>0:16	1/7	-0.35	936839		19.Be3 Nd4 20.Bxd4 Bxd4 21.Nf6+
>>					gxf6 22.Bd5 Bxf2+ 23.Qxf2
>>0:25	1/8	-0.16	1540653		19.Be3 Be6 20.Rac1 Kh8 21.Bxc5
>>					bxc5 22.Rxc5 Nd4 23.Qa3 Rac8 24.Rdc1
>>					Rxc5 25.Rxc5
>>0:48	1/9	-0.41	3195206		19.Be3 Be6 20.Rac1 Rad8 21.Bxc5
>>					bxc5 22.Rc2 Bxd5 23.Bxd5 e4
>>1:02	1/9	-0.30	4191467		19.Bh6 Re6 20.Be3 Nd4 21.Bxd4 Bxd4
>>					22.Rac1 e4 23.Qe2
>>1:16	1/9	0.00	5345593		19.Nf6+ gxf6 20.Bd5 Bd7 21.Bh6
>>					Bf8 22.Qxf6 Re6 23.Bxe6 fxe6 24.Qg5+
>>					Kh8 25.Qf6+ Kg8
>>1:35	1/10	0.00	6997334		19.Nf6+ gxf6 20.Bd5 Bd7 21.Bh6
>>					Bf8 22.Qxf6 Re6 23.Bxe6 fxe6 24.Qg5+
>>					Kh8 25.Qf6+ Kg8
>>3:15	2/11	0.27	15441083	19.Nf6+ gxf6 20.Bd5 Bd7 21.Bh6
>>					Bf8 22.Qxf6 Re6 23.Bxe6 Bxe6 24.Ra3
>>					Bxh6 25.Rg3+ Kf8 26.Qxh6+ Ke7 27.Qh4+
>>					f6 28.Qxh7+ Bf7
>>10:15	3/12	0.36	53030403	19.Nf6+ gxf6 20.Bd5 Bd7 21.Bh6
>>					Bf8 22.Qxf6 Re6 23.Bxe6 Bxe6 24.Ra3
>>					Ne7 25.Bxf8 Rxf8 26.Rg3+ Ng6 27.Qxe5
>>
>>jm
>
>After forcing a few key moves, the problem move appears to be 22.Ra3. I suspect
>that The King engine would need to get to depth 16 for the eval to go above +1,
>which, of course, would take several hours on my machine. Still, though, it
>looks like it has the right plan as soon as it sees Nf6+.
>
>jm


You are doing a bit better than me.  On my laptop (750mhz) it takes Crafty
(current version) 7 minutes to find Nf3+.  Score is 0.00 when it finds it at
depth 12, up from -.35 good for black.  I am going to let it smoke along for
a bit to see if it will go positive, but I believe that the version playing
in the KKUP event went to depth=16 with drawscore so I doubt the current version
will actually find that...  It used to take depth=16, with an 8 hour time limit
on a pentium pro 200, so with today's faster hardware, perhaps it might see
more than 0.00 in a bit...



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.