Author: Thorsten Czub
Date: 03:26:14 08/26/98
Go up one level in this thread
On August 25, 1998 at 22:44:34, fca wrote:
>>Only materialists do.
>
>Agreed. But many chess programs (being materialists or whatever) *do* take the
>poisoned pawn, because search is not enough.
>
>So, it is fair to ask why does Gandalf not play Qxg7?.
It is no materialist. I you would have seen the game:
ChessTiger 11.2 vs. Gandalf from Paderborn, last round
[Event "7th IPCCC"]
[Site "Paderborn"]
[Date "1998.02.15"]
[Round "7"]
[White "ChessTiger 11.2"]
[Black "Gandalf3"]
[Result "0-1"]
1. Nf3 d5 2. g3 e6 3. d4 Nd7 4. Bg2 f5 5. O-O Bd6 6. b3 Qe7 7. c4 c6
8. a4 a5 9. e3 Ngf6 10. c5 Bc7 11. Re1 b6 12. cxb6 Bxb6 13. Ba3 c5
14. Bf1 O-O 15. Nc3 Bb7 16. Rc1 Rac8 17. Bb5 e5 18. Re2 Qe6 19. Nxe5 Nxe5
20. dxe5 Qxe5 21. Bb2 Qe6 22. Rec2 Ng4 23. Qe2 Qh6 24. h4 Rcd8 25. Nd1 d4
26. exd4 cxd4 27. Qe7 Be4 28. Re2 Qf6 29. Bc4+ Kh8 30. Qxf6 Rxf6 31. Rd2 Ne5
32. Be2 Rff8 33. Kh2 Bf3 34. Bb5 Bd5 35. Be2 f4 36. gxf4 Rxf4 37. Kg3 Rdf8
38. Ba3 d3 39. Bh5 Rf3+ 40. Kh2 R8f5 41. Rc8+ Bg8 42. Be8 Bxf2 43. Bd6 R3f4
44. Rxd3 Rxh4+ 45. Kg2 Nxd3 46. Nxf2 Nxf2 47. Bd7 Ne4 48. Bxf5 Nxd6
49. Rxg8+ Kxg8 50. Be6+ 0-1
you would not believe that Gandalf is materialist. I have seen this game
live, and was able to study the evaluations of gandalf DURING the game/moves.
I can tell you as a witness that it has constructed this ATTACK by static
knowledge. The way it made its pieces attack the white king, although the centre
was blocked, and later opened it... so that the hidden pieces had the diagonals
and files to kill white, is typically for the FIGHT of a SEARCH versus a
KNOWLEDGE program.
In the same way Gandalf or CSTal would plan an attack without ANY real chances
to see in the tree, just because they have static evaluation DOING the plan, in
the same way one can estimate HOW they would react in the game we discuss about
(Qxg7??).
I have ordered Gandalf. I hope i will get it soon. You can order it in Steen
Suurballes company and maybe also later at gambit and other distributors.
>I now rephrase:
>**Perhaps** (I do not know, I do not have Gandalf) it rejects Qxg7 (correctly
>so, of course) but **for the wrong reason**... (i.e. on average bad tuning,
>though in this position correct).
There is no WRONG reason is you reject Qxg7.
White is a pawn up. CSTal e.g. evaluates Qxg7 in MINUS because black has
completely development advantages, and all white has it 2 pawns and a queen run
away from different attacking pieces, and a king that will not survive.
There is no other reason. Program having king-safety terms will not play Qxg7...
Thats all. IMO this is a very very good game because it polarized and shows in
example how stupid todays fast and strong chess programs are, BECAUSE they try
to substitute knowledge with search.
>And the point being:
>If I modify the position slightly (making it harder for a black bishop to come
>into play, say) so Qxg7 *is* then a correct move, will Gandalf (andor CSTal)
>still reject it once they see the WQ being driven away and a black rook
>controlling the g-file?
Modify a position and i will set it up in CSTal Win95.
Look, in my tournament programs like zarkov, crafty, cstal, tiger, hiarcs
or more precise :
1 CSTAL WIN95, (6) 4.0 8 13½ 3
2-6 CHESS TIGER 11.5, (12) 3.5 10 16 3
JUNIOR5 BETA JUN.CTG, (5) 3.5 8½ 14 3
CRAFTY 15.17, (22) 3.5(1) 8½ 13 3
CHESS TIGER 11.2, (13) 3.5 7 12½ 2
MCHESS 7.1, (1) 3.5 7 12 3
7-11 HIARCS6, (2) 3.0(1) 9 14½ 2
ZARKOV 4.2C, (23) 3.0 8½ 13½ 3
NIMZO98 PADERBORN, (14) 3.0 7 12½ 2
GENIUS5, (8) 3.0 7 11 2
WCHESS 1.04, (18) 3.0 5½ 11 2
play very very strong. If you study these programs, you will see that they all
found a way to implement knowledge into their programs.
Some more, some less.
All these programs are IMO on the right track. They don't trust search alone.
And they all play nice and good chess, or ?!
I guess most of them would reject Qxg7.
OR ?
>Your views, please?
>
>:-)
>
>Kind regards
>
>fca
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