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Subject: Re: Shredder and missing knowledge for bad-Bishop endgames......

Author: Uri Blass

Date: 16:27:28 08/04/05

Go up one level in this thread


On August 04, 2005 at 19:23:28, Uri Blass wrote:

>On August 04, 2005 at 18:24:58, George Tsavdaris wrote:
>
>>One of Shredder weak points is some wrong-color-Bishop endgames.
>
>It is not a weakness of shredder but weakness of most chess programs in case
>that it is a draw and white cannot force black to play b5 later and win by axb5
>
>It is not obvious for me that it is impossible without analysis so it is not
>obvious for me that it is a draw.
>
>
>I tried the second best program in the world(Fruit2.1)
>
>New game,
>8/8/8/pp6/1P2k3/P1K5/5Bp1/8 w - - 0 1
>
>Analysis by Fruit 2.1:
>
>1.bxa5
>  +-  (1.87)   Depth: 1/1   00:00:00
>1.bxa5 Kd5
>  +-  (1.86)   Depth: 2/7   00:00:00
>1.bxa5 Kd5 2.a6
>  +-  (2.48)   Depth: 3/7   00:00:00
>1.bxa5 Kd5 2.a6 Kc6
>  +-  (2.63)   Depth: 4/7   00:00:00
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3
>  +-  (2.93)   Depth: 5/7   00:00:00
>1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kxb5
>  +-  (3.34)   Depth: 6/11   00:00:00  5kN
>1.bxa5 Kd5 2.a6 Kc6 3.a7 Kb7 4.Kd3 Ka8
>  +-  (3.42)   Depth: 7/11   00:00:00  12kN
>1.bxa5 Kd5 2.a6 Kc6 3.a7 Kb7 4.Kd3 Ka8 5.Bd4
>  +-  (3.71)   Depth: 8/13   00:00:00  26kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.a7 Kb7 5.Bd4 Ka8
>  +-  (3.71)   Depth: 9/13   00:00:00  50kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kc6 5.Kf3 b4 6.axb4
>  +-  (4.48)   Depth: 10/15   00:00:01  91kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.a7 Kb7 5.Ke4 Ka8 6.Kf3 Kb7 7.Kxg2
>  +-  (5.08)   Depth: 11/17   00:00:01  163kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.a7 Kb7 5.Ke4 Ka8 6.Kf3 Kb7 7.Kxg2
>  +-  (5.08)   Depth: 12/18   00:00:01  267kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kc6 5.a7 Kb7 6.Kf3 Ka8 7.Bd4 Kb7 8.Kxg2
>  +-  (5.37)   Depth: 13/22   00:00:01  456kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.a7 Kb7 5.Ke4 Ka8 6.Kf3 Kb7 7.Kxg2 Ka8 8.Bd4
>  +-  (5.64)   Depth: 14/24   00:00:01  769kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kc6 5.Kf3 Kc7 6.Kxg2 Kc6 7.a7 Kb7 8.Bd4 Ka8
>  +-  (5.64)   Depth: 15/28   00:00:01  1259kN
>1.bxa5 Kd5 2.a6 Kc6 3.a7 Kb7 4.Kd3 Ka8 5.Ke4 Kb7 6.Kf3 Ka8 7.Kxg2 Kb7 8.Bd4 Ka8
>9.Kf3
>  +-  (5.90)   Depth: 16/36   00:00:02  2281kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kb8 5.Kf3 Kc7 6.Kxg2 Kb8 7.Bd4 Kc7 8.a7 Kb7
>9.Kf3 Ka8
>  +-  (5.90)   Depth: 17/46   00:00:02  3919kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kb8 5.Kf3 Kc7 6.Kxg2 Kb8 7.Bd4 Kc7 8.a7 Kb7
>9.Kf3 Ka8 10.Ke4
>  +-  (6.17)   Depth: 18/46   00:00:03  5739kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kb8 5.Kf3 Kc7 6.Kxg2 Kb8 7.Bd4 Kc7 8.Kf3 Kc6
>9.a7 Kb7 10.Ke4 Ka8
>  +-  (6.17)   Depth: 19/46   00:00:06  9603kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kb8 5.Kf3 Kc7 6.Kxg2 Kb8 7.Bd4 Kc7 8.Kf2 Kb8
>9.a7+ Kb7 10.Ke3 Ka8 11.Ke4
>  +-  (6.17)   Depth: 20/46   00:00:10  16663kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kb8 5.Kf3 Kc7 6.Kxg2 Kb8 7.Bd4 Kc7 8.a7 Kb7
>9.Kf3 Ka8 10.Ke4 Kb7 11.Kd5 Ka8
>  +-  (6.21)   Depth: 21/48   00:00:16  25943kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kb8 5.Kf3 Kc7 6.Kxg2 Kb8 7.Bd4 Kc7 8.a7 Kb7
>9.Kf3 Ka8 10.Ke4 Kb7 11.Ke5 Ka8 12.Kd5
>  +-  (6.21)   Depth: 22/57   00:00:29  45845kN
>1.bxa5 Kd5 2.a6 Kc6 3.Kd3 Kc7 4.Ke4 Kb8 5.Kf3 Kc7 6.Kxg2 Kb8 7.Bd4 Kc7 8.Kf3 Kb8
>9.Ke4 Kc7 10.Kd5 Kb8 11.Kc6 Ka8 12.Kd5
>  +-  (6.31)   Depth: 23/59   00:00:55  84289kN
>
>(,  05.08.2005)
>
>
>
>>The above is just an example but of course there are thousants similar (E.Nemeth
>>posted many at the past) and this can probably cost at tournaments and I WONDER
>>WHY SMK DOESN'T FIX THIS?!?!?!?
>
>I remember a game when knowledge of Junior that this type of position is a draw
>costed it a point against shredder because shredder forced Junior to play b5 and
>won by axb5.
>
>Uri

Yace also has problems and it is unable to see that the main line is leading to
stalemate.

It may be a draw because of stalemate but there are cases when the stalemate
trick does not work.

New game,
8/8/8/pp6/1P2k3/P1K5/5Bp1/8 w - - 0 1

Analysis by Yace 0.99.87:

1.bxa5
  +-  (2.44)   Depth: 1   00:00:00
1.bxa5
  +-  (2.44)   Depth: 1   00:00:00
1.bxa5 Kd5
  +-  (2.44)   Depth: 2   00:00:00
1.bxa5 Kd5
  +-  (2.44)   Depth: 2   00:00:00
1.bxa5 Kd5 2.a6
  +-  (2.78)   Depth: 3   00:00:00
1.bxa5 Kd5 2.a6
  +-  (2.78)   Depth: 3   00:00:00
1.bxa5 Kd5 2.a6 Kc6
  +-  (2.88)   Depth: 4   00:00:00
1.bxa5 Kd5 2.a6 Kc6
  +-  (2.88)   Depth: 4   00:00:00
1.bxa5 Kd5 2.a6 Kc6 3.Bg1
  +-  (3.06)   Depth: 5   00:00:00
1.bxa5 Kd5 2.a6 Kc6 3.Bg1
  +-  (3.06)   Depth: 5   00:00:00
1.bxa5 Kd5 2.a6 b4+ 3.axb4 g1B
  +-  (3.46)   Depth: 6/9   00:00:00  4kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kxb5
  +-  (3.90)   Depth: 6/10   00:00:00  5kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kxb5
  +-  (3.90)   Depth: 6/10   00:00:00  12kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kxb5
  +-  (3.90)   Depth: 7/10   00:00:00  17kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kxb5
  +-  (3.90)   Depth: 7/13   00:00:00  30kN
1.bxa5 Kd5 2.Bd4 Kc6 3.a4 g1Q 4.Bxg1 bxa4
  +-  (3.50)   Depth: 8/13   00:00:00  36kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.a4 bxa4
  +-  (3.14)   Depth: 8/13   00:00:00  42kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.a4 bxa4
  +-  (3.14)   Depth: 8/15   00:00:00  78kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.a4 bxa4 5.Kxa4
  +-  (3.14)   Depth: 9/15   00:00:00  97kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.a4 bxa4 5.Kxa4
  +-  (3.14)   Depth: 9/17   00:00:00  156kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.a4 bxa4 5.Ba7 Kd6 6.Kxa4
  +-  (2.95)   Depth: 10/17   00:00:00  198kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.a4 bxa4 5.Ba7 Kd6 6.Kxa4
  +-  (2.95)   Depth: 10/23   00:00:00  336kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.a4 bxa4 5.Ba7 Kd6 6.Kxa4
  +-  (2.95)   Depth: 11/23   00:00:00  419kN
1.Bg1 a4 2.Kd2 Kf3 3.Kd3 Kg3 4.Kd4 Kf3 5.Kc5 Kf4
  +-  (2.96)   Depth: 11/23   00:00:00  530kN
1.Bg1 a4 2.Kd2 Kf3 3.Kd3 Kf4 4.Ke2 Kf5
  +-  (3.11)   Depth: 11/23   00:00:00  577kN
1.Bg1 a4 2.Kd2 Kf3 3.Kd3 Kf4 4.Ke2 Kf5
  +-  (3.11)   Depth: 11/26   00:00:01  697kN
1.Bg1 a4 2.Kd2 Kd5 3.Bc5 Kc4 4.Kc2 Kd5 5.Kd3 Ke5 6.Ke2 Kf5
  +-  (3.21)   Depth: 12/26   00:00:01  841kN
1.Kd2 Ke5
  +-  (3.22)   Depth: 12/26   00:00:02  1099kN
1.Kd2 Ke5 2.Kd3 Kd5 3.Be3 Kd6 4.Ke4 Ke6 5.Kf3 a4 6.Kxg2
  +-  (3.24)   Depth: 12/26   00:00:02  1378kN
1.Kd2 Ke5 2.Kd3 Kd5 3.Be3 Kd6 4.Ke4 Ke6 5.Kf3 a4 6.Kxg2
  +-  (3.24)   Depth: 12/26   00:00:02  1462kN
1.Kd2 Ke5 2.Kd3 Kd5 3.Be3 a4 4.Bd4 Kd6 5.Bc5+ Kd5 6.Kd2 Kc4 7.Kc2 Kd5 8.Kd3 Ke5
9.Ke2 Kd5 10.Kd2 Kc4 11.Kc2 Kd5 12.Kd3 Ke5 13.Ke2 Kd5 14.Kd2
  +-  (3.21)   Depth: 13/27   00:00:03  1778kN
1.bxa5 Kd5 2.a6 Kc6 3.a7 b4+ 4.axb4 Kb7
  +-  (3.22)   Depth: 13/27   00:00:04  2001kN
1.bxa5 Kd5 2.a6 Kc6 3.a7 b4+ 4.axb4 Kb7
  +-  (3.64)   Depth: 13/27   00:00:04  2029kN
1.bxa5 Kd5 2.a6 Kc6 3.a7 b4+ 4.axb4 Kb7
  +-  (4.64)   Depth: 13/27   00:00:04  2063kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kc5 Kb8 5.Kc6 g1Q 6.Bxg1 Ka8 7.a7 b4
  +-  (7.00)   Depth: 13/27   00:00:05  2395kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kc5 Kb8 5.Kc6 g1Q 6.Bxg1 Ka8 7.a7 b4
  +-  (7.00)   Depth: 13/27   00:00:05  2689kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kc5 Kb8 5.Kc6 g1Q 6.Bxg1 Ka8 7.Kc7 b4
  +-  (7.03)   Depth: 14/27   00:00:08  3331kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kc5 Kb8 5.Kc6 g1Q 6.Bxg1 Ka8 7.Kc7 b4
  +-  (7.03)   Depth: 14/27   00:00:10  4346kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kc5 Kb8 5.Kc6 g1Q 6.Bxg1 Ka8 7.Kc7 b4 8.axb4
  +-  (7.03)   Depth: 15/27   00:00:15  5547kN
1.bxa5 Kd5 2.a6 Kc6 3.Kb4 Kc7 4.Kc5 Kb8 5.Kc6 g1Q 6.Bxg1 Ka8 7.Kc7 b4 8.axb4
  +-  (7.03)   Depth: 15/32   00:00:19  6953kN

(,  05.08.2005)




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