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Subject: Re: High NPS vs. Low NPS

Author: Uri Blass

Date: 03:40:10 11/26/01

Go up one level in this thread


On November 26, 2001 at 06:26:52, Steve Maughan wrote:

>The answer lies in the structure of the programs and the evaluation functions.
>
>The King aka ChessMaster evaluates the control of each square on the board.
>This information is useful for guiding the search and using in the evaluation
>function however it's expensive to compute.  You can also see this with Phalanx
>which can triggers a deaper search from within the evaluation function - i.e.
>the evaluation says that the position is not stable so search another ply
>deeper.
>
>In contrast you can get some programs (Goliath) that use a piece-table
>evaluation and rely on Null Move and some simpler extensions to get by.

What do you mean by piece-table evaluation?
Goliath does not use piece-table evaluation

you cannot evaluate passed pawn only by piece square table and it seems that
goliath knows to evaluate passed pawns and here is the proof:

goliath can see positive score for white inspite of the fact that it does not
see the promotion

Goliath Light 1.5 - Blass,U
7k/7r/2pp4/2p5/2p5/8/PK6/7R w - - 0 1

Analysis by Goliath Light 1.5:

1.Rxh7+ Kxh7 2.Kc3 Kg6 3.a4 Kf5
  ▓  (0.57)   Depth: 6/8   00:00:00
1.Rxh7+ Kxh7 2.a4 Kg6 3.a5 d5 4.a6 Kf5 5.Kc3
  ▓  (0.29)   Depth: 6/12   00:00:00  3kN, tb=2
1.Rxh7+ Kxh7 2.a4 Kg6 3.a5 d5 4.a6 Kf5 5.Kc3
  ▓  (0.29)   Depth: 7/12   00:00:00  4kN, tb=2
1.Rxh7+ Kxh7 2.a4 Kg6 3.a5 d5 4.a6 Kf5 5.Kc3
  ▓  (0.29)   Depth: 7/14   00:00:00  6kN, tb=4
1.Rxh7+ Kxh7 2.a4 Kg6 3.a5 d5 4.a6 Kf5 5.Kc3
  ▓  (0.29)   Depth: 8/14   00:00:00  8kN, tb=4
1.Rxh7+ Kxh7 2.a4 Kg6 3.a5 d5 4.a6 Kf5 5.Kc3
  ▓  (0.59)   Depth: 8/14   00:00:00  12kN, tb=10
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.Kc2 c3 5.a6 Kg7 6.a7
  ▒  (1.05)   Depth: 8/14   00:00:00  17kN, tb=16
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.Kc2 c3 5.a6 Kg7 6.a7
  ▒  (1.05)   Depth: 9/14   00:00:00  19kN, tb=16
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 Kg6
  ▒  (1.11)   Depth: 9/23   00:00:00  45kN, tb=30
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 Kg6
  ▒  (1.11)   Depth: 10/23   00:00:00  56kN, tb=30
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 Kg6
  +-  (1.44)   Depth: 10/23   00:00:00  74kN, tb=67
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 Kg6
  +-  (2.27)   Depth: 10/23   00:00:00  77kN, tb=81
1.Rxh7+
  +-  (2.27)   Depth: 10/23   00:00:00  91kN, tb=85
1.Rxh7+
  +-  (2.27)   Depth: 11/23   00:00:00  100kN, tb=85
1.Rxh7+
  +-  (2.58)   Depth: 11/24   00:00:00  137kN, tb=124
1.Rxh7+
  +-  (3.39)   Depth: 11/24   00:00:00  185kN, tb=153
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 Kg6 5.a7 Kf5 6.a8Q Kf4 7.Kc1 c3 8.Qxc6
  +-  (4.28)   Depth: 11/26   00:00:00  249kN, tb=158
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 Kg6 5.a7 Kf5 6.a8Q Kf4 7.Kc1 c3 8.Qxc6
  +-  (4.28)   Depth: 12/26   00:00:00  266kN, tb=158
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 Kg6 5.a7 Kf5 6.a8Q Kf4 7.Kc1 c3 8.Qxc6
  +-  (4.58)   Depth: 12/27   00:00:00  339kN, tb=207
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 d3 5.Kc3 Kg6 6.a7 Kf5 7.a8Q Kf4 8.Qf8+ Ke4
9.Qxc5
  +-  (4.77)   Depth: 12/27   00:00:00  434kN, tb=237
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 d3 5.Kc3 Kg6 6.a7 Kf5 7.a8Q Kf4 8.Qf8+ Ke4
9.Qxc5
  +-  (4.77)   Depth: 13/27   00:00:00  499kN, tb=237
1.Rxh7+ Kxh7 2.a4 d5 3.a5 d4 4.a6 d3 5.Kc3 Kg6 6.a7 Kf5 7.a8Q Kf4 8.Qf8+ Ke4
9.Qxc5
  +-  (5.07)   Depth: 13/27   00:00:01  732kN, tb=328
1.Rxh7+ Kxh7 2.Kc3 d5 3.a4 Kg6 4.a5 Kf5 5.a6 Ke5
  +-  (5.31)   Depth: 13/27   00:00:01  1297kN, tb=386
1.Rxh7+ Kxh7 2.Kc3 d5 3.a4 Kg6 4.a5 Kf5 5.a6 Ke5
  +-  (5.31)   Depth: 14/27   00:00:02  1514kN, tb=386
1.Rxh7+ Kxh7 2.Kc3 d5 3.a4 Kg6 4.a5 Kf5 5.a6 Ke5
  +-  (5.61)   Depth: 14/29   00:00:02  2089kN, tb=535

(Blass, Tel-aviv 26.11.2001)



  These
>are fast - it's probably not fair to say they are dump since they get their
>knowledge from the seach.  Just a different way of "skinning the cat".
>
>Regards,
>
>Steve

How do you know this information about goliath and chessmaster?
The source code of Goliath or Chessmaster is not free so the only way that you
can know is if you talk with the programmers.

Uri



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