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Subject: Re: a simple test position that is hard for Shredder and hiarcs7.32

Author: Uri Blass

Date: 16:15:52 01/04/02

Go up one level in this thread


On January 04, 2002 at 18:58:34, Uri Blass wrote:

>On January 04, 2002 at 17:35:01, Gian-Carlo Pascutto wrote:
>
>>Bleh! Sjeng sees that Nxb5 loses in a few seconds, but it does
>>not find any better move!
>>
>>The score for Nxb5 is now -1.2 or so and Sjeng does not
>>fail high on the other moves, so it would still play it
>>after more than 10 minutes thought.
>
>After Nxb5 Rf5 the advantage of black
>is clearly bigger than +1.2
>
>+1.2 is not a winning advantage and after Nxb5 tiger saw +4
>
>I believe that one of
>Ne4 or g3(the move that tiger expected) or Re1
>are better(I am not sure if they save the game but they should be better from
>computer point of view)
>
>Everything seems to avoid Nxb5 after enough time and I expect sjeng to play a
>different move if you give it enough time.
>
>
>Here is yace's opinion
>
>after 1.g3
>
>New position
>8/5rbk/6q1/1p1Q4/1PpP2p1/2N2pP1/5P2/3R2K1 b - - 0 1
>
>Analysis by Yace 0.99.56:
>
>1...Rf5 2.Qe4
>  ³  (-0.46)   Depth: 3   00:00:00
>1...Rf5 2.Qd7 Qh5
>  ³  (-0.61)   Depth: 3   00:00:00
>1...Rf5 2.Qd7 Qh5
>  ³  (-0.61)   Depth: 3   00:00:00
>1...Rf5 2.Qd7 Qh5
>  ³  (-0.61)   Depth: 3   00:00:00
>1...Rf5 2.Qd7 Qh5 3.Re1
>  ³  (-0.49)   Depth: 4   00:00:00
>1...Rf5 2.Qd7 Qh5 3.Re1 Rg5
>  ³  (-0.46)   Depth: 5   00:00:00  3kN
>1...Qf5 2.Qxb5 Qxb5 3.d5 Qxd5 4.Rxd5
>  ³  (-0.47)   Depth: 5   00:00:00  5kN
>1...Qf5 2.Qxb5 Qxb5 3.Nxb5 Rb7 4.Nc3
>  ³  (-0.61)   Depth: 5   00:00:00  5kN
>1...Qf5 2.Qxb5 Qxb5 3.Nxb5 Rb7 4.Nc3 Rxb4
>  ³  (-0.61)   Depth: 6   00:00:00  14kN
>1...Qf5 2.Qxb5 Qxb5 3.Nxb5 Rb7 4.Nc3 Rxb4 5.Kf1
>  ³  (-0.56)   Depth: 7   00:00:00  35kN
>1...Qf5 2.Qxb5 Qxb5 3.Nxb5 Rb7 4.Nd6 Rxb4 5.Nf5 c3 6.Nxg7
>  ³  (-0.65)   Depth: 8   00:00:00  154kN
>1...Qf5 2.Qxb5 Qxb5 3.Nxb5 Rb7 4.Nd6 Rxb4 5.Nf5 Bf6 6.d5 c3
>  ³  (-0.67)   Depth: 10   00:00:02  1183kN
>1...Rf5 2.Qb7 Rh5 3.Nxb5 Qh6 4.Qe4+ Kg8 5.Qxg4 Rxb5 6.Qc8+ Kh7 7.d5 Qg5 8.Qxc4
>  ³  (-0.68)   Depth: 10   00:00:04  1603kN
>1...Rf5 2.Qb7 Rh5 3.Ra1 Qh6 4.Qe4+ Kh8 5.Ra8+ Bf8 6.Rxf8+ Qxf8 7.Qxg4 Qf7 8.Kf1
>  µ  (-0.93)   Depth: 10   00:00:05  2014kN
>1...Rf5 2.Qe4 Rh5 3.Re1 Qxe4 4.Rxe4 Bf8 5.Re5 Rxe5 6.dxe5 Bxb4 7.Nxb5 c3
>  µ  (-0.99)   Depth: 11   00:00:08  3639kN
>1...Rf5 2.Qe4 Rh5 3.Re1 Qxe4 4.Rxe4 Bf8 5.Re5 Kg6 6.Rxb5 Rxb5 7.Nxb5 Bxb4
>  µ  (-0.97)   Depth: 12   00:00:14  5789kN
>1...Rf5 2.Qe4 Rh5 3.Re1 Qxe4 4.Rxe4 Bf8 5.Re5 Kg6 6.Rc5 Bxc5 7.dxc5 Kf5 8.Nxb5
>Ke5
>  µ  (-0.91)   Depth: 13   00:00:28  11708kN
>1...Rf5 2.Qe4 Rh5 3.Re1 Qxe4 4.Rxe4 Bf8 5.Rxg4 Bxb4 6.Ne4 Kh6 7.Rf4 Rd5 8.Rxf3
>Rxd4 9.Rf6+ Kg7
>  µ  (-1.02)   Depth: 14   00:01:10  28264kN
>
>(Blass, Tel-aviv 05.01.2002)
>
>After Nb5 Rf5 yace fails low again and again and
>I did not give it enough time to finish depth 12
>
>New position
>[D]8/6bk/6q1/1N1Q1r2/1PpP2p1/5p2/5PP1/3R2K1 w - - 0 1
>
>Analysis by Yace 0.99.56:
>
>2.Qxf5 Qxf5
>  -+  (-4.40)   Depth: 1   00:00:00
>2.Qxc4
>  +-  (1.80)   Depth: 1   00:00:00
>2.Qxc4 Rh5
>  +-  (1.49)   Depth: 2   00:00:00
>2.Qxc4 Rh5 3.Kf1
>  +-  (1.70)   Depth: 3   00:00:00
>2.Qxc4 Qb6 3.Nc3 Rh5
>  +-  (1.48)   Depth: 4   00:00:00
>2.Qxc4 g3 3.gxf3 Rxf3 4.fxg3 Rxg3+ 5.Kf1
>  +-  (1.50)   Depth: 5   00:00:00  17kN
>2.Qxc4 g3 3.gxf3 Rxf3 4.Rb1 Qxb1+ 5.Kg2
>  ±  (1.10)   Depth: 6   00:00:00  31kN
>2.Qxc4 g3 3.gxf3 Rxf3 4.Qc1 Rxf2 5.Kh1
>  ²  (0.28)   Depth: 6   00:00:00  31kN
>2.Qd7 Rxb5 3.Qxb5 fxg2
>  ²  (0.29)   Depth: 6   00:00:00  31kN
>2.Qd7 Rh5 3.Qc8 Rxb5 4.gxf3
>  ²  (0.28)   Depth: 6   00:00:00  31kN
>2.Qxc4 g3 3.gxf3 Rxf3 4.Qc1 Rxf2 5.Kh1
>  ²  (0.28)   Depth: 6   00:00:00  31kN
>2.Qxc4 g3 3.gxf3 Rxf3 4.Kf1 Rxf2+ 5.Kg1 Qf5 6.Rc1
>  =  (0.19)   Depth: 7   00:00:00  312kN
>2.Qxc4 Qh5 3.Qc2 g3 4.gxf3 gxf2+ 5.Qxf2 Rxb5 6.Qc2+ Kg8
>  =  (-0.17)   Depth: 8   00:00:03  1074kN
>2.Qxc4 Qh5 3.Qc2 g3 4.gxf3 gxf2+ 5.Qxf2 Rxb5 6.Kf1 Qh3+ 7.Qg2 Qxg2+ 8.Kxg2 Kg6
>9.d5
>  ³  (-0.32)   Depth: 9   00:00:07  2273kN
>2.Qxc4 Qh5 3.Qc2 g3 4.gxf3 gxf2+ 5.Qxf2 Rg5+ 6.Kf1 Qh3+ 7.Qg2 Rxg2 8.Ke1
>  µ  (-0.72)   Depth: 10   00:00:11  4155kN
>2.Qxc4 g3 3.gxf3 Rxf3 4.Kg2 Qe4 5.Kg1 gxf2+ 6.Kf1 Qc2 7.Qxc2+ Kg8
>  -+  (-1.43)   Depth: 10   00:00:32  11453kN
>2.Qxc4 g3 3.gxf3 Qh5 4.fxg3 Qxf3 5.Qc2 Qxg3+ 6.Kh1 Qg6 7.Qh2+ Rh5 8.Na3 Rxh2+
>9.Kxh2
>  -+  (-1.83)   Depth: 11   00:00:49  17447kN
>2.Qxc4 Qh5 3.g3 Qh3 4.Qf1 Qxf1+ 5.Kxf1 Rh5 6.Kg1 Rxb5 7.d5 Rxb4 8.d6 Rd4 9.Rxd4
>  -+  (-2.61)   Depth: 11   00:01:17  26933kN
>2.Qxc4 g3 3.gxf3 Qh5 4.fxg3 Qxf3 5.Qc2 Qxg3+ 6.Kh1 Qf3+ 7.Kg1 Kg8 8.Nd6 Qg3+
>9.Qg2 Qe3+ 10.Kh2 Rh5+ 11.Qh3 Rxh3+ 12.Kg2
>  -+  (-3.01)   Depth: 12   00:03:17  68881kN
>2.Qxc4 g3 3.gxf3 Rxf3 4.Kg2 Qe4 5.Kg1 gxf2+ 6.Kf1 Qg6 7.Qd3 Rxd3 8.Kxf2
>  -+  (-4.01)   Depth: 12   00:03:57  81979kN
>2.Qxc4 g3 3.fxg3 f2+ 4.Kf1 Qh5 5.Qd3 Qh1+ 6.Ke2 f1Q+ 7.Rxf1 Qxf1+ 8.Kd2 Qxd3+
>9.Kxd3 Rxb5 10.Kc4 Rg5 11.d5 Rxg3
>  -+  (-5.02)   Depth: 12   00:05:27  112849kN
>
>(Blass, Tel-aviv 05.01.2002)
>
>
>Uri

after finishing depth 12 here is yace's line

2.Qe4 Rxb5 3.Qe1 Bf8 4.d5 Rxb4 5.Qe6 c3 6.Qd7+ Kg8 7.Qc6 Qc2 8.Qe6+ Kg7
  -+  (-4.02)   Depth: 12   00:17:44  381827kN

(Blass, Tel-aviv 05.01.2002)

yace agrees that Nxb5 is losing more than 4 pawns
when other moves do not lose so much.

g3 was only one example and yace believes that
black advantage is less than 1 pawn after a move like Ne4
that seems better than g3 to me(only 0.61 pawns
after some minutes)

Uri



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