Author: Vincent Diepeveen
Date: 05:03:25 06/22/00
Go up one level in this thread
In games versus crafty you usual can escape to a draw in open positions with
queens, as it misses checks in qsearch. Take this objectively as that this
is not a complaint against crafty, because on the other hand crafty
searches non-checking lines usual deeper because of not doing checks in
qsearch.
The only risk i run with diep is that it wants to win too much in those
queen pos.
At fics old diep version (last linux compile from months ago)
runs under diep against a crafty.
Move diep roboElvis
1. d4 (0:01) Nf6 (0:01)
2. c4 (0:00) e6 (0:00)
3. Nf3 (0:00) d5 (1:40)
4. Nc3 (0:00) c5 (0:00)
5. cxd5 (0:00) Nxd5 (0:00)
6. e3 (0:00) Nc6 (0:00)
7. Bc4 (0:00) cxd4 (1:41)
8. exd4 (0:00) Bb4 (1:40)
9. Qd3 (0:00) Nb6 (2:40)
10. Bb3 (2:56) Nd7 (0:01)
11. Qd1 (1:43) O-O (1:18)
12. O-O (1:41) Nf6 (0:05)
13. Bg5 (1:33) h6 (1:31)
14. Bf4 (0:04) Na5 (1:16)
15. Ba4 (0:23) Nc4 (1:53)
16. Qb3 (1:18) Bxc3 (1:12)
17. bxc3 (1:16) Na5 (0:49)
18. Qc2 (1:15) Nd5 (0:01)
19. Bg3 (1:15) Bd7 (0:07)
20. Bxd7 (1:07) Qxd7 (0:04)
21. Ne5 (1:10) Qd8 (0:06)
22. Rfc1 (1:17) Rc8 (1:17)
23. Qb2 (0:00) a6 (1:25)
24. c4 (1:10) Ne7 (1:10)
25. Qb4 (0:00) Nf5 (1:09)
26. Nf3 (0:01) Re8 (1:06)
27. Be5 (1:11) f6 (1:07)
28. Bg3 (1:11) Re7 (0:12)
29. d5 (1:00) exd5 (0:16)
30. cxd5 (0:53) Rxc1+ (0:13)
31. Rxc1 (0:56) Rd7 (0:11)
32. Qe1 (0:56) Kh8 (1:32)
33. Bf4 (1:07) g5 (0:00)
34. Bd2 (1:31) Rxd5 (0:01)
35. Bc3 (1:33) Nc6 (0:00)
36. Qe6 (1:01) Nfd4 (1:08)
37. Nxd4 (1:01) Nxd4 (0:06)
38. Qe4 (0:54) Rc5 (0:14)
39. h4 (0:45) Rc4 (1:20)
40. hxg5 (1:00) hxg5 (1:07)
41. f4 (0:52) Qb6 (1:07)
42. Qe8+ (0:00) Kg7 (1:05)
43. Qe7+ (0:00)
{Still in progress} *
Qb6? Diep directly saw a draw!
diep(C)(2177)[27] whispers: pv = 00:21 950233 (96172) 9 -0.15 h4xg5 h6xg5
\ Bc3-b2 Rc4xc1 Bb2xc1 Nd4-c6 Qe4-f3 Kh8-g7 Bc1-b2 Qd8-d6
fics%
diep(C)(2177)[27] whispers: pv = 00:46 4915150 (1081413) 9 -0.12 f2-f4 Qd8-b6
\ Qe4-e8 Kh8-g7 Qe8-e7 Kg7-g6 Qe7-e8 Kg6-f5 Qe8-d7 Nd4-e6 Kg1-h1 Qb6-c6
\ Qd7-d3 Kf5xf4
fics%
diep(C)(2177)[27] whispers: pv = 00:48 2237499 (417374) 10 0.00 Qe4-e8 Kh8-g7
\ Qe8-e7 Kg7-g6 Qe7-e8 Kg6-f5 Qe8-d7 Kf5-g6 Qd7-e8
fics%
diep(C)(2177)[27] whispers: pv = 00:33 1446958 (247075) 10 0.00 Qe8-e7 Kg7-g6
\ Qe7-e8 Kg6-f5 Qe8-d7 Kf5-g6 Qd7-e8
I didn't see kibitzes from crafty. I wonder what depth crafty sees
Qb6 is a draw.
Vincent
On June 22, 2000 at 07:55:53, Vincent Diepeveen wrote:
>On June 21, 2000 at 11:12:23, Robert Hyatt wrote:
>
>>On June 21, 2000 at 11:03:42, David Rasmussen wrote:
>>
>>>I find that a lot of the games that my program loses, it loses because it
>>>doesn't search checking moves in qsearch.
>>>Anyway, how do people do that most effectively? I would like not to generate all
>>>moves in the qsearch (just the captures), but then I will miss the noncapturing
>>>checks.
>>
>>
>>I did them in Cray Blitz, and in early versions of Crafty. But I haven't
>>done checks in the q-search since just prior to the Jakarta WMCCC event.
>>
>>You can control them to an extent... ie when you get to the q-search, you
>>can consider a check. But if you look at a capture at the first ply or 2,
>>then there is little point in doing checks deeper in the q-search because the
>>'stand pat' will allow you to avoid the checks totally, earlier in the
>>tree.
>
>76% of all checks give a cutoff in DIEP in qsearch
>on average a check improves score with 2.9 pawns
>
>But it's hard to figure out what checks to do and what you don't need
>to do. It's simply hard work, but possible for everyone to do.
>
>It's hundreds of lines of code in DIEP.
>
>>I personally don't do them because I don't like the q-search at all. It is
>>unreliable, and way too selective to trust. You show me a position where the
>>best q-search move is a check (say a capturing check) and I'll show you a
>>position where the best response to a capture is _not_ another capture, but
>>rather a quiet move that pins or indirectly attacks something. The q-search
>>misses way too much. I think it is more profitable to make your basic search
>>better by extending in the right places, since it already has no real inherent
>>pruning errors other than a lack of depth. I'd like to drive the q-search to
>>almost nothing, as that would eliminate many errors.
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