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Subject: Re: A proposed WAC replacement for testing

Author: Uri Blass

Date: 10:51:18 09/19/01

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On September 19, 2001 at 12:47:33, Bruce Moreland wrote:

>On September 19, 2001 at 05:29:27, Uri Blass wrote:
>
>>On September 19, 2001 at 03:54:57, Bruce Moreland wrote:
>>
>>>I ran for two minutes per position in K=2 mode, and here is what I came up with.
>>>
>>>It's hard to decide exactly what constitutes a cook.  In purest sense, a cook
>>>should be a mate that is no slower than the key allows.
>>>
>>>I think that positions with approximately the same large score could be
>>>confusing, and I found a lot of those.
>>>
>>>I would throw these out, to be safe.
>>>
>>>Your mileage may vary.
>>>
>>>bruce
>>>
>>>---------------
>>>
>>>Id:  ECM.973
>>>Fen: 2r2bk1/4qp2/3n2p1/2R1p1Np/2p1N3/r6P/1Q3PP1/3R2K1 w - - 0 1
>>>Qxa3 is +3, the key, Rxc8 is +4.
>>
>>1.Qxa3 Ne4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7
>>
>>I believe that 5.Rxf8+ is winning for white but programs need time to find this
>>move and usually prefer at small depthes Re8 that probably leads to a draw
>>
>>If Ferret evalutes 5.Re8 as +3 and not +1 for white then it seems that it has a
>>poblem in it's evaluation function
>>
>>Here is Junior's evaluation for 5.Re8
>>
>>It needs very small depth and less than 1 second on p200 to understand that the
>>score should not be +3 for white
>>
>>Deep Fritz also does not see +3 score for white.
>
>You can't say that I have a problem because other programs fail low quickly
>after you give then ten plies for free.  My program only searched 12 plies here,
>from the root.

If I give Deep Fritz to search the position 2 plies after the root
it does not see something close to +3 evaluation.

New position
[D]2r2bk1/4qp2/3n2p1/2R1p1Np/2p1N3/Q6P/5PP1/3R2K1 b - - 0 1

Analysis by Deep Fritz:

1...Rxc5 2.Qxc5 Nxe4
  +-  (2.41)   Depth: 1/7   00:00:00
1...Nxe4!
  +-  (1.97)   Depth: 1/8   00:00:00
1...Nxe4! 2.Nxe4 Rxc5
  =  (0.03)   Depth: 1/8   00:00:00
1...Nxe4 2.Nxe4 Rxc5 3.Nxc5 Qxc5
  =  (0.03)   Depth: 2/8   00:00:00
1...Nxe4 2.Nxe4 Rxc5 3.Nxc5 Qxc5
  =  (0.03)   Depth: 3/12   00:00:00  1kN
1...Nxe4--
  ²  (0.34)   Depth: 4/12   00:00:00  2kN
1...Nxe4--
  ²  (0.34)   Depth: 4/12   00:00:00  3kN
1...Nb5!
  ²  (0.31)   Depth: 4/13   00:00:00  5kN
1...Nb5! 2.Qg3
  ²  (0.28)   Depth: 4/13   00:00:00  6kN
1...Nb5--
  ²  (0.59)   Depth: 5/15   00:00:00  9kN
1...Nb5-- 2.Qe3 Rxc5 3.Rd7 Qxd7 4.Nf6+ Kg7
  +-  (1.53)   Depth: 5/15   00:00:00  17kN
1...Nxe4!
  +-  (1.50)   Depth: 5/15   00:00:00  21kN
1...Nxe4! 2.Nxe4 Rxc5 3.Nxc5 Qxc5 4.Qc3 Bd6
  ²  (0.28)   Depth: 5/16   00:00:00  26kN
1...Nxe4--
  ²  (0.59)   Depth: 6/15   00:00:00  39kN
1...Nxe4--
  ²  (0.59)   Depth: 6/15   00:00:00  43kN
1...Nxe4 2.Nxe4 Rxc5 3.Nxc5 Qxc5 4.Qxc5 Bxc5 5.Rc1 f5 6.Rxc4
  ²  (0.59)   Depth: 7/15   00:00:00  83kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qb6 5.Rxf8+ Kxf8 6.Nxc5
  ±  (0.81)   Depth: 8/20   00:00:00  171kN
1...Nxe4--
  ±  (1.12)   Depth: 9/22   00:00:00  346kN
1...Nxe4-- 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qb6
  ±  (1.16)   Depth: 9/24   00:00:00  455kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qb6 5.Qa8 Qb1+ 6.Kh2 Kg7 7.Rxf8
  ±  (1.16)   Depth: 10/24   00:00:01  1125kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8
  ±  (0.97)   Depth: 11/25   00:00:03  2329kN
1...Nxe4--
  ±  (1.28)   Depth: 12/28   00:00:05  4153kN
1...Nxe4--
  ±  (1.28)   Depth: 12/28   00:00:06  4841kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8
  ±  (1.22)   Depth: 13/27   00:00:15  11766kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8
  +-  (1.41)   Depth: 14/30   00:00:44  32131kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8
  ±  (1.31)   Depth: 15/32   00:01:43  74836kN

(Blass, Tel-aviv 19.09.2001)

>
>My program likes Rxc8 better, but it has a good score for Qxa3, because in the
>final position white is up a queen for a rook and a pawn.

In the final position that I see in Deep Fritz's pv it is a queen for rook and 2
pawns so if we speak only about material it is 2 pawn advntage for white.

Black has also a positional advantage because it has a passed pawn and the
knight is not close to the passed pawn.

I believe that Deep Fritz does not consider the fact that the knight is not
close to the passed pawn but it considers the fact that black has a dangerous
passed pawn.

Note that tiger also has similiar evaluation to Ferret and here is tiger's
analysis 2 plies after the root:
New position
2r2bk1/4qp2/3n2p1/2R1p1Np/2p1N3/Q6P/5PP1/3R2K1 b - - 0 1

Analysis by Chess Tiger 14.0:

1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qb6 5.Rxf8+ Kxf8 6.Qxc5+ Qxc5 7.Nxc5
  +-  (2.52)   Depth: 10   00:00:00  106kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qb6 5.Rxf8+ Kxf8 6.Nxc5 Qb1+ 7.Kh2 f6
  +-  (2.08)   Depth: 10   00:00:00  116kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6
  +-  (2.08)   Depth: 11   00:00:00  205kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qb6 5.Qa8 Kg7 6.Rxf8 Qb1+ 7.Kh2 Rb5
  +-  (2.90)   Depth: 12   00:00:01  431kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8 c3 8.Qa6
Be7
  +-  (3.30)   Depth: 13   00:00:05  1388kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8 c3 8.Qa6
Be7 9.Nd6
  +-  (3.14)   Depth: 14   00:00:10  2795kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8 c3 8.Qc1
c2 9.Nf6 Rc3
  +-  (3.10)   Depth: 15   00:00:20  5562kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8 c3 8.Qc1
c2 9.Nf6 Rc4 10.Nd7 Ba3
  +-  (2.96)   Depth: 16   00:00:47  12426kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8 c3 8.Qc1
c2 9.Nf6 Rc4 10.Nd7 Bg7
  +-  (3.04)   Depth: 17   00:01:38  25831kN
1...Nxe4 2.Nxe4 Rxc5 3.Rd7 Qe6 4.Rd8 Qe7 5.Re8 Qxe8 6.Nf6+ Kh8 7.Nxe8 c3 8.Qc1
c2 9.Nf6 Rc6 10.Nd5 f6
  +-  (2.68)   Depth: 18   00:04:56  78795kN

(Blass, Tel-aviv 19.09.2001)

Uri



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