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Subject: Re: New Test (was Test Position. Hard pawn endgame)

Author: Robert Hyatt

Date: 09:11:51 10/01/01

Go up one level in this thread


On September 30, 2001 at 11:12:47, Uri Blass wrote:

>On September 30, 2001 at 10:39:50, Miguel A. Ballicora wrote:
>
>>On September 30, 2001 at 06:15:44, José Carlos wrote:
>>
>>>On September 29, 2001 at 20:15:16, Gareth McCaughan wrote:
>>>
>>>>José Carlos wrote:
>>>>
>>>>>  The point is not the move, but the eval. The program must
>>>>> know white is winning:
>>>>>
>>>>> [D]R4rk1/5pp1/5q1p/1p1Qp3/8/1B6/1PP2bPP/5K2 w - - 0 1
>>>>>
>>>>>  Qxf7+ and after the changes, the pawn ending is won.
>>>>
>>>>Crafty 18.11, Athlon 1GHz, has +0.8 after 0.4 seconds (8 ply),
>>>>rising to 0.93 after 11 seconds, 1.17 after 28 seconds, 1.36
>>>>after 6 minutes. It plays Qxf7+ at all depths.
>>>>
>>>>--
>>>>g
>>>
>>>  It doesn't surprise me at all. Crafty is probably the best in the world
>>>evaluatiing pawn endgames.
>>>
>>>  José C.
>>
>>Anyway, the position "as is" is not perfect for a test because white will want
>>to play Qxf7 even if doesn't understand the upcoming pawn endgame (because Qxf7
>>just win a pawn).
>
>No
>
>Junior7 prefers to force a draw by perpetual check and
>cannot find Qxf7.
>
>If a program believes that black is better in the pawn endgame
>then it is not going to find Qxf7.

If a program believes black is better in that position after the trades,
then it already has a serious endgame problem (lack of knowledge).  Nothing
else matters in such cases...


>
>
> What is very good is the idea, so I try to improve the
>>original position in a way that the first move gives an idea that the program
>>understand the endgame.
>>
>>[D]8/4k1p1/1p2B2p/4p3/8/4P2P/1PP1KbP1/8 b - - am Bxe3;
>>
>>Crafty 17.14 avoids Bxe3 in an instant without any problem even in my K6-II 400
>>mhz. How about other programs? The test is simple but I like it in the modified
>>version because it tells me fi a program understand a couple of concepts.
>>For instance, Gaviota wants to play Bxe3, So I know what to modify :-).
>>
>>Regards,
>>Miguel
>
>Deep Fritz also likes Bxe3
>New position
>8/4k1p1/1p2B2p/4p3/8/4P2P/1PP1KbP1/8 b - - 0 1
>
>Analysis by Deep Fritz:
>
>1...Kxe6--
>  ±  (1.19)   Depth: 1/3   00:00:00
>1...Kxe6--
>  ±  (1.19)   Depth: 1/3   00:00:00
>1...Bxe3!
>  ²  (0.44)   Depth: 1/4   00:00:00
>1...Bxe3!
>  =  (-0.13)   Depth: 1/4   00:00:00
>1...Bxe3 2.Bd5
>  =  (-0.13)   Depth: 2/5   00:00:00
>1...Bxe3 2.Bd5 Kd6
>  =  (-0.16)   Depth: 3/6   00:00:00
>1...Bxe3 2.Bf5 Kf6 3.Be4
>  =  (-0.06)   Depth: 4/7   00:00:00
>1...Bxe3 2.Bd5 Kd6 3.c4 Bd4
>  =  (-0.06)   Depth: 5/8   00:00:00  1kN
>1...Bxe3 2.Bd5 Bc5 3.g3 g6 4.c4
>  =  (-0.03)   Depth: 6/10   00:00:00  3kN
>1...Bxe3 2.Bd5 Bc5 3.g3 g6 4.Be4 Kf6
>  =  (-0.03)   Depth: 7/11   00:00:00  7kN
>1...Bxe3 2.Bd5 Bc5 3.g3 g6 4.Be4 Kf6 5.c3
>  =  (0.00)   Depth: 8/12   00:00:00  16kN
>1...Bxe3 2.Bf5 Bc1 3.b4 Bb2 4.c4 Ba3 5.Be4
>  =  (0.03)   Depth: 9/15   00:00:00  50kN
>1...Bxe3 2.Bd5 Kd6 3.Be4 Bf4 4.b4 b5 5.Bd3 Kc6 6.c4 bxc4
>  =  (0.09)   Depth: 10/15   00:00:00  99kN
>1...Bxe3 2.Bf5 Bc1 3.b3 Bf4 4.Be4 Kd6 5.c4 Kc5
>  =  (0.09)   Depth: 11/17   00:00:00  231kN
>1...Bxe3 2.Bf5 Bc1 3.b3 Bf4 4.Be4 Kd6 5.b4 h5 6.g4 hxg4 7.hxg4
>  =  (0.09)   Depth: 12/19   00:00:01  483kN
>1...Bxe3 2.Kxe3 Kxe6 3.c4 h5 4.g4 g6 5.b4 h4 6.Ke4 g5 7.c5
>  =  (0.19)   Depth: 13/21   00:00:02  1039kN
>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.Ke4 h5 5.h4
>  =  (0.25)   Depth: 14/22   00:00:03  1611kN
>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.Ke4 Ke6 5.b3 h5 6.h4
>  =  (0.25)   Depth: 15/23   00:00:06  3076kN, tb=1
>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.b4 Ke6 5.Ke4
>  ²  (0.41)   Depth: 16/24   00:00:12  5395kN, tb=6
>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.b4 h5 5.g4 hxg4 6.hxg4 Kd7 7.Ke4
>  ²  (0.50)   Depth: 17/25   00:00:25  11346kN, tb=50
>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.b4 h5 5.Ke4 Ke6 6.h4 Kd6 7.c5+
>  ²  (0.56)   Depth: 18/27   00:00:47  21088kN, tb=198
>1...Bxe3 2.Kxe3 Kxe6 3.c4 h5 4.h4 Kf5 5.b4 Ke6 6.Ke4 Kf6 7.c5
>  ²  (0.59)   Depth: 19/30   00:01:54  49750kN, tb=993
>
>(Blass, Tel-aviv 30.09.2001)
>
>Note that finding Kxe3 is also not an easy problem
>for part of the programs
>
>Deep Fritz has no problem but Junior7 cannot find it
>
>I remember that I told Amir Ban some years ago about
>pawn endgames problems and he told me that it is not important
>because Junior almost never does not get pawn endgames
>so it is more important for him to work about other problems
>in the evaluation.

:)

Funny comment.  Which will change after playing a lot of GM players.  :)


>
>I also heard that the book of Junior does not
>include a lot of captures and I guess that it reduces
>the chances for a pawn endgame(I do not know if it is
>still the case today and I heard it few years ago).
>
>Here is Junior7's opinion after 1...Bxe3
>
>New position
>[D]8/4k1p1/1p2B2p/4p3/8/4b2P/1PP1K1P1/8 w - - 0 1
>
>Analysis by Junior 7:
>
>2.Kxe3 Kxe6 3.Ke4 h5 4.h4
>  =  (0.23)   Depth: 3   00:00:00
>2.Kxe3 Kxe6 3.Ke4 g5 4.c3 h5
>  =  (0.08)   Depth: 6   00:00:00  1kN
>2.Bf5 Bc1 3.b4 Kf6
>  =  (0.09)   Depth: 6   00:00:00  2kN
>2.Bd5 Bf4 3.Kf3 Kf6
>  =  (0.17)   Depth: 6   00:00:00  3kN
>2.Bd5 Bc1 3.b4 Kf6 4.Be4 h5
>  =  (0.19)   Depth: 9   00:00:00  11kN
>2.Bd5 Bc1 3.b3 Kd6 4.Be4 b5 5.h4 h5
>  =  (0.19)   Depth: 12   00:00:00  61kN
>2.Bd5 Bc1 3.b3 Kf6 4.g3 h5 5.Kf3 b5
>  =  (0.19)   Depth: 15   00:00:00  307kN
>2.Bf5 Bc1 3.b4 h5 4.Be4 Bb2 5.c4 Ba3
>  =  (0.23)   Depth: 15   00:00:01  519kN, tb=1
>2.Bf5 Bc1 3.b4 Kf6 4.Be4 h5 5.g3 g6 6.c4 Ba3 7.b5 Bc5
>  =  (0.17)   Depth: 18   00:00:03  1908kN, tb=4
>2.Bd5 Kd6 3.Be4 Bf4 4.c3 b5 5.Kf3 Bc1 6.b3 h5 7.b4
>  ²  (0.26)   Depth: 18   00:00:08  4485kN, tb=5
>2.Bd5 Bc1 3.b4 Kf6 4.Kf3 Bd2 5.b5 h5 6.Ke4 Bc3 7.h4
>  ²  (0.27)   Depth: 20   00:00:21  11362kN, tb=36
>2.Bd5 Bc1 3.b4 Kf6 4.Be4 h5
>  ²  (0.29)   Depth: 22   00:00:44  23743kN, tb=131
>2.Bd5 Bf4 3.Kd3 Kf6 4.Ke4 Bc1 5.b3 Bd2
>  ²  (0.31)   Depth: 23   00:02:07  66154kN, tb=448
>2.Bd5 Bc1 3.b4 Kf6 4.g3 h5 5.Kd3 g6 6.c3 Kf5 7.Be4+ Kg5 8.c4 Ba3 9.h4+ Kg4 10.b5
>Kxg3
>  ²  (0.28)   Depth: 24   00:03:28  104526kN, tb=1104
>2.Bd5 Bc1 3.b4 Kf6 4.g3 h5 5.Kd3 Bb2 6.Ke4 Bc3 7.b5 Kg5
>  ²  (0.28)   Depth: 25   00:05:30  163531kN, tb=2868
>
>(Blass, Tel-aviv 30.09.2001)
>
>Uri



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