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Subject: Re: Fritz defeats itself at Leiden!

Author: Robert Hyatt

Date: 21:05:27 05/20/01

Go up one level in this thread


On May 19, 2001 at 15:56:53, Vine Smith wrote:

>On May 19, 2001 at 12:29:46, Sune Larsson wrote:
>
>>On May 19, 2001 at 11:33:42, Vine Smith wrote:
>>
>>>On May 19, 2001 at 10:46:48, Sune Larsson wrote:
>>>
>>>>On May 19, 2001 at 10:15:06, Vine Smith wrote:
>>>>
>>>>>On May 19, 2001 at 08:52:03, Sune Larsson wrote:
>>>>>
>>>>>>On May 19, 2001 at 06:22:23, Vine Smith wrote:
>>>>>>
>>>>>>>On May 19, 2001 at 05:26:07, Jeroen Noomen wrote:
>>>>>>>
>>>>>>>>Fritz - Gambit Tiger   Leiden round 4
>>>>>>>>-------------------------------------
>>>>>>>>1. d4 d5 2. c4 dxc4 3. e4 Nc6 4. Be3 Nf6 5. Nc3 e5 6. d5 Na5 7. Nf3 Bd6
>>>>>>>>8. Qa4+ Bd7 9. Qxa5 a6 10. Na4 Qe7 11. a3 Nxe4 12. Bxc4 b5 13. Bd3 Nf6
>>>>>>>>14. Nc3 e4 15. Nxe4 Nxe4 16. O-O O-O 17. Rfe1 f5 18. h3 Qf7 19. Rad1 Rfe8
>>>>>>>>20. Bc2 g6 21. b4 Nc3 22. Rd3 Qg7 23. Bd1 Ne4 24. Bd4 Qf7 25. Rde3 g5
>>>>>>>>26. Bc2 g4 27. hxg4 fxg4 28. Bxe4 gxf3 29. Bxf3 Qf4 30. Bc5 Qh2+ 31. Kf1
>>>>>>>>Bf4 32. Rxe8+ Bxe8 33. Be3 Bd6 34. Ke2 Bh5 35. Rd1 Qe5 36. Rd4 Bxf3+
>>>>>>>>37. gxf3 Qf5 38. Rd3 h5 39. a4 h4 40. axb5 h3 41. Qa1 h2 42. b6 cxb6
>>>>>>>>43. Qh1 Rc8 44. f4 Qh5+ 45. Kf1 Rc2 46. Bd2 Bxf4 47. d6 Rxd2 48. Rxd2 Bxd2
>>>>>>>>49. d7 Qd1+ 50. Kg2 Qxh1+ 0-1
>>>>>>>
>>>>>>>Astonishing positional suicide -- few, if any, humans would ever play 21.b4,
>>>>>>>entombing the queen. Of course, Tiger could afford to open the game in any way
>>>>>>>it pleased after that. It would be interesting to see if the lack of interest in
>>>>>>>liberating the queen is duplicated by many programs; correct or not, I would
>>>>>>>have been so concerned about this offside post that I would have played 17.Qe1
>>>>>>>immediately.
>>>>>>
>>>>>>
>>>>>> The terms "mobility" and "king safety" comes to mind after this kamikaze...
>>>>>>
>>>>>> Anyway, I made a quick check on PIII 800 with 128 Mb hash. 4 min ponder.
>>>>>>
>>>>>> Fritz 5.32        21.b3  and later plays b3-b4.
>>>>>> Fritz 6 Old       21.b3
>>>>>> Fritz 6 (Newest)  21.b4
>>>>>> Deep Fritz        21.b4
>>>>>> Hiarcs 7.32       21.b4
>>>>>>
>>>>>> Then we have some non closers:
>>>>>>
>>>>>> Crafty 18.08      21.Bc1
>>>>>> Shredder 5        21.h4
>>>>>> Gandalf 4.32h     21.Kf1 or 21.Re2  (shifting after 4.02)
>>>>>>
>>>>>> Sune
>>>>>
>>>>>Horrible that not only Fritz, but also Deep Fritz (this program is going to play
>>>>>Kramnik???) and Hiarcs (with something of a good reputation for positional play,
>>>>>I thought) commit this blunder. Also, any program that doesn't evaluate the
>>>>>resulting position at something like -2.00 or lower has nothing to be proud of.
>>>>>I'm putting together a suite of positional problems to evaluate programs'
>>>>>understanding or lack thereof, and I'll have to include this position as an
>>>>>"avoid move" type of problem (even though it's a little unfair to Fritz, which
>>>>>will of course fail this one).
>>>>
>>>>
>>>>>Can you tell if Gandalf wants to play 21.Re2 in order to follow up with 22.Qe1?
>>>>>If so, that would mark it as the only program so far to demonstrate some concern
>>>>>about the queen's situation.
>>>>>
>>>>>Regards,
>>>>>Vine
>>>>
>>>> Gandalf ponders about lines like 21.Re2 Nf6 22.Ng5 Qe7 23.Qc3, but
>>>> after some 8 minutes again shifts to 21.Kf1 b4 22.a4 = (Gandalf)
>>>>
>>>> Sune
>>>
>>>Ugh! This suggests some generalized failure of program evaluation routines. Even
>>>in Gandalf's line with 21...b4 22.a4, having the queen cut off in this manner
>>>seems fatal. I'm going to investigate whether very long-term searches will
>>>correct this fault, which would at least give these programs the hope that with
>>>the faster hardware of tomorrow, they could avoid such disastrous decisions.
>>>
>>>Regards,
>>>Vine
>>
>> Long-term searches here would sure be interesting - as your coming suite of
>> positional problems. The latter must be pure gold for the programmers, if
>> it's possible to pinpoint down just what the positions are all about - and
>> transform them into programming language...
>>
>> Sune
>
>Fritz 6e at 17 ply still doesn't think it has done a bad thing. It currently
>believes that in reply to 21.b4, Black should play 21...Re7, evaluating the
>position at +0.03. In the entire line it gives, there is no effort made to free
>the queen from her prison. I'm hoping that it will see the light within the next
>3 or 4 ply -- or come up with some astounding method of liberating the queen
>with no bad side effects.
>I started working on the positional suite in connection with a program a friend
>of mine is going to write. I'm arguing for some radical new approach to
>evaluation, but, indeed, the challenge is to formulate it in such a way that he
>can code it successfully. Maybe I'll get lucky and stumble across a new
>frontier.
>The suite is meant to show that something new might be necessary. I have about
>120 positions now, but I keep having to review and replace them after I look at
>test runs. It's difficult -- unlike tactical problems, it's often impossible to
>absolutely prove the validity of some positional continuations. So I try to find
>positions where some particularly fine positional move has been endorsed and
>explained by several IMs and/or GMs in varying sources. But also some very
>elementary problems as well -- many programs have been failing these too. When I
>have something consistent and grouped into useful themes for diagnostic
>purposes, I'd be glad to release it in EPD format to anyone interested.
>
>Regards,
>Vine

Just as a note, crafty has a couple of terms here that are preventing it from
falling into the b4 hole.  1.  King safety doesn't like the queen stuck on the
off-side of the board with no hope to get over to the kingside;  2.  the
usual blocked pawns/levers evaluation makes totally blocking things up very
hard..




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