Author: Jeremiah Penery
Date: 23:53:17 02/12/01
Go up one level in this thread
On February 13, 2001 at 02:02:37, Dann Corbit wrote:
>I have been fooling around with a special compile of Yace, and it got 294/300 on
>WAC at 5 seconds per position on my machine. I let Yace have the 6 it missed at
>60 seconds per position. Upon scrutiy, I have found that there are some
>positions in my WAC test set that are clearly in error.
>
>white ( 1): input: st 60
>white ( 1): input: test wac60.ci
>title position 041
>Stored 0 learned positions into hash table
>solution Ka5 Kc5
...
> 44923 2.386 Mat21 8t 1.b7 Rg5+ 2.Kc6 Rg6+ 3.Kd7 Kxb7 {EGTB} {80}
...
> 2823031 58.990 Mat12 14f. 1.Ka5 Rg1 2.Rf8+ Kb7 3.g8=Q Ra1+ 4.Kb4 Rb1+
> 5.Ka3 Ra1+ 6.Kb2 Ra5 7.Qg2+ Ka6 8.Qc6 Rb5+
> 9.Kc2 Rc5+ 10.Qxc5 {EGTB} 10...Kb7 11.Ra8 Kxa8
> 12.Qc8#! {1081}
>Move b7 is a mate in 21, and yet is not listed among the solutions. That is
>clearly an error.
I think you posted this before, and it was agreed to be a cook. However, it was
also said that this test was really written for humans, and that Ka5/Kc5 are the
much better human moves. Also, they do lead to a mate a lot faster, so they
could be considered better moves than b7.
>title position 100
>Stored 0 learned positions into hash table
>solution b6+
...
> 35515876 52.292 2.92 20t 1.Kb3 Bd6 2.Kc2 Bc7 3.Kd3 Bd6 4.Ke3 Bc7 5.Bc3
> Bd8 6.Kd3 Kb8 7.Kc2 Ka7 8.Kb2 Be7 9.Kb3 Bd8
> 10.Ka4H Be7H 11.Bd2H {HT}
> 36207255 53.290 2.93 20t+ 1.Ka3 Kb8
> 39780878 58.990 2.93 20t 1.Ka3 Kb8
> 39780878 58.993 2.93 20u. 1.Ka3 Kb8
>Curious about this one. Are Be3, Ke3, and Ka3 bad moves? They seem to deliver
>a decisive advantage, but I will admit I have not studied the board position
>recently. Let's see, here it is:
<fixed diagram, hopefully>
[D]8/k1b5/P4p2/1Pp2p1p/K1P2P1P/8/3B4/8 w - -
This is almost surely computer mis-evaluation. b6 is really the only way to
break open the position and win, but I think there might be a way to win with
Be3 and playing b6 or something later. I think someone else posted that an
IM/GM found that solution, but I might remember wrong.
>title position 141
>Stored 0 learned positions into hash table
>solution Qxf4
...
>This one (WAC 141) was just a little slow. Took 14 seconds to find the right
>answer and 25 seconds to recognize a checkmate.
This is a big null-move-killer problem. If you turn null-move off, you should
find it 2-3 plies earlier.
>title position 146
>Stored 0 learned positions into hash table
>solution Bc8
...
> 2228454 58.997 Mat51 14u. 1.Bd3 Ke3 2.c5 Kxd3 3.cxd6 {EGTB} 3...f2! 4.d7!
> f1=Q! 5.d8=Q! Qc1+! 6.Kd7! Qc4 7.d6! Qa4+!
> 8.Ke7! Qe4+! 9.Kf7 Qd5+ 10.Ke8! Qh5+! 11.Kd7!
> Qb5+! 12.Kc8! Qa6+! 13.Kb8! Qb5+! 14.Ka7! Qa4+!
> 15.Kb7! Qb5+! 16.Qb6! Qd7+! 17.Kb8! Kd2 18.Qc7!
> Qe8+! 19.Qc8! Qe5 20.Qc6! Ke2! 21.Qc4+ Kd2
> 22.Qb4+! Ke2 23.Kb7! Qg7+! 24.Kc6! Qg2+ 25.Kc7!
> Qg3! 26.Qc4+! Kf2! 27.Qd5! Qc3+ 28.Qc6! Qg3!
> 29.Kb7! Ke1! 30.d7 Qb3+! 31.Kc8! Qh3! 32.Qf6!
> Ke2! 33.Kc7! Qh7! 34.Qe6+ Kf1! 35.Qd5 Qh2+!
> 36.Kc6! Qc2+! 37.Kb6! Qf2+! 38.Ka5! Qe1+!
> 39.Kb5! Qb1+! 40.Kc5! Kg1 41.d8=Q! Qc1+ 42.Qc4
> Qa3+! 43.Qb4 Qa7+ 44.Qbb6 Qxb6+! 45.Qxb6! Kg2
> 46.Qf6 Kh2 47.Qg6 Kh3 48.Kd5 Kh4 49.Ke4! Kh3
> 50.Kf3! Kh4 51.Qh6# {1001}
>Since Bd3 is a checkmate, it is surely a correct solution to the problem.
This was also discussed a couple times in the past here. Bc8 leads to mate in
20, and is a much nicer solution. I guess for a computer that all the solutions
should be included, but for a human Bc8 should be the solution.
>title position 230
>Stored 0 learned positions into hash table
>solution Rb4
...
> 33737137 58.992 1.87 16f. 1...Rh7 2.Rb1 a4 3.Ba3 Rh5 4.f4 Bb7 5.Bb2 Rh8
> 6.Ra1 Kb5 7.Kg2 Bc6 8.Rh1 Rb8 9.Kf3 {80}
>Here, Yace really just missed it. But I think 230 is probably the hardest one
>in the set.
Definitely. I'm pretty sure Rb4 is the only way to win, but I think it's partly
a null-move thing and also a passed-pawn thing. I had some version of Crafty
where I increased certain pawn-scoring and extensions a lot and WAC230 was
solved very quickly.
Jeremiah
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