Author: Uri Blass
Date: 15:51:55 02/06/04
Go up one level in this thread
On February 06, 2004 at 15:37:03, Drexel,Michael wrote:
>On February 06, 2004 at 15:03:49, Uri Blass wrote:
>
>>On February 06, 2004 at 14:29:30, Thorsten Czub wrote:
>>
>>>On February 06, 2004 at 12:19:09, Uri Blass wrote:
>>>
>>>>Here is the line of the game that you posted
>>>>
>>>>14...Qc7 {-0.30/18} 15. Bxh6 gxh6 {-0.40/15} 16. Qxh6 Rfd8 {-0.54/16}
>>>>17.Rd3 Nh7 {0.00/17} 18.f4 Bf8 {0.01/18} 19.Rg3+ Kh8 {0.01/18} 20. Qh5 Rab8
>>>>{0.35/17} 21.f5 exf5 {0.85/16} 22.Rf1 Rd7 {0.84/19} 23.Rxf5 f6 {0.84/18
>>>>
>>>>You can see that shredder evaluated the position as 0.54 pawns for itself at
>>>>move 16 and it is more than 0.30 pawns for itself at move 14.
>>>
>>>right. right.
>>>but it is 18 searches deep !
>>>
>>>in move 20 (that is 12 searches away from Qc7 it feels negative, and in move
>>>21 even morenegative.
>>>
>>>how can the program oversee this, when it sees the things different within
>>>12 plies later.
>>>
>>>>I believe that not pruning could not help shredder to avoid Qc7 and I am also
>>>>not sure if it was the losing error(I suggested 17...Ne8 instead of 17...Nh7).
>>>>
>>>>Uri
>>>
>>>shredder itself changes the score from + into minus within a few moves.
>>>
>>>in between there is the fritz-like 0,00.
>>>
>>>if shredder itself sees now the weakness, why wasn't it able to see the obvious
>>>move earlier ? it pruned it away-
>>>if the move was wrong, why the score dropping ??
>>
>>I believe that the following claims are correct:
>>
>>1)The move Bxh6 was wrong but shredder blundered later(I suggested 17...Ne8
>>instead of 17...Nh7)
>>
>
>No,Bxh6 is not wrong. White can at least draw.
>CS Tal would never accept a draw and lose but that's another story of course.
>
>>2)Shredder searched 15.Bxh6 to reduced depth but this is not the reason for
>>playing 14...Qc7(otherwise shredder could see a drop in the score immediatly
>>after 15.Bxh6 and it did not happen)
>>
>>Uri
>
>There is probably not a single program that can find the _only_ defence 17...Ne8
>18.Bd3 Bd8 since white can play 19.Nd5.
>
>Michael
This is possible only at move 16.
I remember that I tried yace and yace could learn a draw score after 17...Nh7
but when I went back it suggested 17...Ne8 with a positive score.
I am not sure about the result but the idea is 17...Ne8 18.f4 Bf8 19.Rg3+ Bg7
20.f5 exf5 21.exf5 f6
I do not have shredder8 but shredder7.04 can see 0.01 pawns for black at depth
13 and 0.06 for black at depth 14 and I think that black has better chances than
the game when black had to give the pawn f6.
CSTal2.03 - Shredder8
[D]r2rn1k1/2q3b1/p1bp1p1Q/1p3P2/8/P1N3R1/1PP1B1PP/1K5R w - - 0 1
Analysis by Shredder 7.04:
22.Rxg7+ Nxg7 23.Qxf6
µ (-1.33) Depth: 1/2 00:00:00
22.Rxg7+ Qxg7
-+ (-1.56) Depth: 1/4 00:00:00
22.Re1
± (1.15) Depth: 1/4 00:00:00
22.Re1
± (1.15) Depth: 1/4 00:00:00
22.Re1 Qf7
± (0.74) Depth: 2/4 00:00:00
22.Re1 Qf7
± (0.74) Depth: 2/4 00:00:00
22.Re1 Kf8 23.Qe3
± (0.99) Depth: 3/12 00:00:00
22.Re1 Qf7 23.Bh5
± (1.02) Depth: 3/12 00:00:00
22.Re1 Qe7 23.Bc4+ Kf8 24.Nxb5 Bxh6
± (0.77) Depth: 4/12 00:00:00
22.Re1 Qe7 23.Rg4 Qe5
± (0.74) Depth: 4/12 00:00:00
22.Re1 d5 23.Bh5 Qxg3 24.Qh8+ Kxh8
² (0.49) Depth: 5/12 00:00:00
22.Re1 d5 23.Rg4 d4 24.Nd1
² (0.45) Depth: 5/14 00:00:00
22.Re1 d5 23.Rg4 d4 24.Rxg7+ Nxg7 25.Qh7+ Kxh7
= (0.20) Depth: 6/14 00:00:00 29kN
22.Re1 d5 23.Qh4 Qe5 24.Rg6 Qxf5 25.Bd3
= (0.06) Depth: 6/20 00:00:00 61kN
22.Rd1 d5 23.Qh4 d4 24.Rxd4 Be4
= (0.07) Depth: 6/20 00:00:00 65kN
22.Rd1 d5 23.Qh4 Qe5 24.Qh5 Nd6
= (0.10) Depth: 6/20 00:00:00 68kN
22.Bf3 Kf8 23.Qg6 Qf7 24.Bxc6 Qa2+ 25.Kxa2
= (0.11) Depth: 6/20 00:00:01 105kN
22.Bf3 d5 23.Qg6 b4 24.axb4 Rab8
= (0.20) Depth: 6/20 00:00:01 115kN
22.Bf3 d5 23.Qg6 Qf7 24.Qh6 Qc7 25.Qg6 Qf7 26.Qh6 Qc7 27.Qg6
= (0.00) Depth: 7/20 00:00:01 157kN
22.Re1 d5 23.Qh4 Qe5 24.Rg6 Qxf5 25.Bd3 Qf4
= (0.01) Depth: 7/20 00:00:01 164kN
22.Re1 d5 23.Qh4 d4 24.Na2 Bd5 25.Nb4 Rac8
= (0.06) Depth: 7/20 00:00:02 200kN
22.Re1 d5 23.Qh4 d4 24.Na2 Bd5 25.Nb4 Rac8 26.Rg6
= (0.01) Depth: 8/24 00:00:04 540kN
22.Bf3 d5 23.Rg4 d4 24.Bxc6 Qxh2 25.Qxh2
= (0.02) Depth: 8/24 00:00:04 576kN
22.Bf3 d5 23.Rg4 Qe5 24.Qg6 Rac8 25.Rd1 Kh8 26.Bxd5
= (0.18) Depth: 8/24 00:00:05 610kN
22.Bf3 d5 23.Rg4 Qe5 24.Qg6 a5 25.Rh4 b4 26.Qh7+ Kf8 27.axb4 axb4 28.Nxd5
= (0.09) Depth: 9/24 00:00:07 925kN
22.Rg4 d5 23.Bd3 Qe5 24.Qg6 Kf8
= (0.10) Depth: 9/24 00:00:10 1268kN
22.Rg4 d5 23.Bd3 Qe5 24.Qg6 Rac8 25.Rh4 Kf8 26.Qf7+ Kxf7
= (0.10) Depth: 9/24 00:00:10 1298kN
22.Rg4 d5 23.Bf3 Rac8 24.Re1 d4 25.Bxc6 dxc3 26.Rxe8+ Rxe8 27.Qh7+ Kxh7
= (-0.10) Depth: 10/24 00:00:16 2083kN
22.Re1 d5 23.Qh4 d4 24.Na2 Rac8 25.Bd3 Bb7 26.Rg6 Qc5 27.Re6
= (-0.09) Depth: 10/26 00:00:17 2168kN
22.Re1 d5 23.Qh4 d4 24.Na2 Rac8 25.Bd3 Bb7
= (-0.05) Depth: 10/28 00:00:20 2559kN
22.Bf3 d5 23.Qg6 Qf7 24.Qh6 d4 25.Bxc6 Qd5 26.Nxd5
= (-0.04) Depth: 10/28 00:00:20 2642kN
22.Bf3 d5 23.Qg6 Qf7 24.Qh6 Qc7 25.Qg6 Qf7 26.Qh6 Qc7 27.Qg6
= (0.00) Depth: 10/28 00:00:21 2760kN
22.Qh4 d5 23.Bd3 d4 24.Ne2 Bd5 25.Re1 a5
= (0.01) Depth: 10/28 00:00:25 3287kN
22.Qh4 d5 23.Bd3 a5 24.Bxb5 Bxb5 25.Nxb5 Qc4 26.Rxg7+ Nxg7 27.Qh7+ Kxh7
= (0.01) Depth: 10/28 00:00:26 3451kN
22.Qh4 d5 23.Bd3 d4 24.Ne2 Qe5 25.Re1 Rac8 26.Rg4 Bd5 27.Nxd4
= (0.19) Depth: 11/32 00:00:46 5913kN
22.Qh4 d5 23.Bd3 Rac8 24.Re1 d4 25.Ne2 Qa5 26.Rg6 Bb7 27.Nf4
= (0.12) Depth: 12/32 00:01:17 9830kN
22.Qh4 d5 23.Bd3 Nd6 24.Qxf6 Qf7 25.Qe5 Kf8 26.f6 Bxf6
= (-0.01) Depth: 13/32 00:02:38 20662kN
22.Qh4 d5 23.Bd3 Rab8 24.Re1 a5 25.Na2 d4 26.Rh3 Bd7 27.Qh5 Bf8
= (-0.06) Depth: 14/36 00:06:27 50438kN
(Blass, Tel-Aviv 07.02.2004)
Uri
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