Author: Robert Hyatt
Date: 19:09:36 07/22/00
Go up one level in this thread
On July 22, 2000 at 19:17:26, Ed Schröder wrote:
>On July 22, 2000 at 16:03:59, Amir Ban wrote:
>
>>On July 22, 2000 at 15:32:26, Ed Schröder wrote:
>>
>>>On July 22, 2000 at 14:16:51, Andrew Dados wrote:
>>>
>>>>On July 22, 2000 at 14:11:20, Ed Schröder wrote:
>>>>
>>>>>On July 22, 2000 at 13:28:28, blass uri wrote:
>>>>>
>>>>>>Deeper blue had a positive evaluation before trading queens.
>>>>>>
>>>>>>The evaluation of Deeper blue was based on Deeper blue's logfile
>>>>>>
>>>>>>9(6) 3 T=46 34...Qxf1
>>>>>>10(6) 2 T=130 34...Qxf1
>>>>>>11(6) 2 T=168 34...Qxf1
>>>>>>
>>>>>>The evaluation when deeper blue started to ponder (hash guess Rxf1) was
>>>>>>
>>>>>>7 (4) -30
>>>>>>7 (6) -66
>>>>>>8 (6) -50
>>>>>>9 (6) -50
>>>>>>10 (6) -50
>>>>>>11 (6) -48
>>>>>>
>>>>>>Deeper blue lost 0.5 pawn in the evaluation and the only reason that I can
>>>>>>explain it is that it is a root processor.
>>>>>>
>>>>>>I guess that something like this cannot happen to Deep Junior because it is
>>>>>>probably more knowledge based program.
>>>>>>
>>>>>>Uri
>>>>>
>>>>>The behavior you describe is quite normal. After a queen exchange in the
>>>>>next move often other more accurate tables are used which may cause such
>>>>>score differences. I do the same in Rebel. That doesn't make the program
>>>>>a root processor. A root processor is a program that totally (or to a
>>>>>great extend) relies on the evaluation on the root. If you read the IBM
>>>>>pages it is said DB has something similar (a short investigation at the
>>>>>root). That makes DB no root processor.
>>>>>
>>>>>Ed
>>>>
>>>>What you just said is pretty much confirmation of preprocessing to me:
>>>>'After a queen exchange in the next move often other more accurate tables are
>>>>used []'...
>>>>If it is done in the search - then no score differences should be seen; if it is
>>>>done at root then it is clear preprocessing...
>>>>
>>>>-Andrew-
>>>
>>>Yes such ticks are preprocessing. And it helps. But note that in Rebel
>>>only a few things are done this way not more than being < 0.5% of the
>>>total knowledge. That makes Rebel not a root processor and DB neither
>>>which was my reply to header of the subject.
>>>
>>>Ed
>>
>>I disagree.
>>
>>Even if only a small part is preprocessed, the effect here is huge: half a pawn.
>>DB played 37... Qxf1+ into an even position and woke up a move later into a
>>half-pawn disadvantage. This means that according to its own evaluation Qxf1 is
>>a blunder and would never have been played if not for preprocessing.
>>
>>DB switched from Qe2 (-21) to Qxf1+ (+2) and then learned that it's actually
>>Qxf1+ (-48). So Qe2 was clearly better by DB evaluation.
>>
>>Junior evaluates Qe2 and Qxf1+ as equals.
>>
>>Amir
>
>When I run Rebel (which has no pre-processing stuff in this position) the
>Rebel score for white goes up to from about -0.06 to +0.55 on deeper plies
>after 34..Qe2 35.Qxe2 Bxe2 and after 34..Qxf1+ 35. Rxf1 the score remains
>about equal, slightly worse for white (-0.15). This means a score difference
>of 0.70 between Qe2 and Qxf1+ in favor of Qxf1+ the move played by DB
>which makes it actually more complicated to judge if we have case here of
>an infamous pre-processor mistake (or not) as after all the good move is
>played (in Rebel's view of course).
>
>Below is the Rebel analysis, maybe you or Uri can filter out something
>important as for me it is impossible to judge which of the moves is
>better as this position is beyond my understanding.
>
>And maybe you should run Junior a bit longer and see if Qe2 in the end
>also is refuted.
>
>Ed
>
>Rebel's log-file. Note that I have given the moves 34..Qe2 35.Qxe2 Bxe2
>in advance to speed-up things a bit.
>
>[Event "?"]
>[Site "?"]
>[Date "1997.05.03"]
>[Round "?"]
>[White "Garry Kasparov"]
>[Black "Deep Blue 2"]
>[Result "1-0"]
>[WhiteElo "?"]
>[BlackElo "?"]
>[ECO "A07"]
>
>1.Nf3 d5 2.g3 Bg4 3.b3 Nd7 4.Bb2 e6 5.Bg2 Ngf6 6.O-O c6 7.d3 Bd6 8.Nbd2
>O-O 9.h3 Bh5 10.e3 h6 11.Qe1 Qa5 12.a3 Bc7 13.Nh4 g5 14.Nhf3 e5 15.e4
>Rfe8 16.Nh2 Qb6 17.Qc1 a5 18.Re1 Bd6 19.Ndf1 dxe4 20.dxe4 Bc5 21.Ne3
>Rad8 22.Nhf1 g4 23.hxg4 Nxg4 24.f3 Nxe3 25.Nxe3 Be7 26.Kh1 Bg5 27.Re2
>a4 28.b4 f5 29.exf5 e4 30.f4 Bxe2 31.fxg5 Ne5 32.g6 Bf3 33.Bc3 Qb5
>34.Qf1 Qe2 35.Qxe2 Bxe2
>
>00:00:04 9.00 -0.09 36.Re1 Bf3 37.Rf1 Kf8 38.Bxf3 exf3
> 39.Bxe5 Rxe5 40.Rxf3 Rde8 41.Ng4
> Re1 42.Kg2 (3)
>
>00:00:05 9.01 -0.06 36.Kg1 Bf3 37.Rf1 Rd7 38.Bxe5 Bxg2
> 39.Ng4 Bxf1 (4)
>
>00:00:12 10.00 0.03 36.Kg1 Bf3 37.Rf1 b5 38.Bxf3 exf3
> 39.Bxe5 Rxe5 40.Rxf3 Kg7 41.Ng4
> Re1 42.Kf2 (8)
>
>00:00:32 11.00 0.31 36.Kg1 Bh5 37.Bxe5 Rxe5 38.g4 Bxg6
> 39.fxg6 Kg7 40.Re1 Rde8 41.Nc4 R5e6
> 42.Nd2 (15)
>
>00:01:07 12.00 0.41 36.Kg1 Bh5 37.Bxe5 Rxe5 38.g4 Bxg6
> 39.fxg6 Kg7 40.Re1 Rde8 41.Nc4 R5e6 (38)
>
>00:02:33 13.00 0.55 36.Kg1 Bf3 37.Bxf3 exf3 38.Kf2 c5
> 39.bxc5 Rc8 40.Rh1 (80)
>
>00:04:02 14.00 0.55 36.Kg1 Bf3 37.Bxf3 exf3 38.Kf2 c5
> 39.bxc5 Rc8 40.Rh1 (182)
I get the same behavior, except my score is quite a bit higher. I switch
to Kg1 quickly and stick with it, with the score climbing each iteration...
nss depth time score variation (1)
7 0.70 -0.41 36. Bxe5 Rxe5 37. Re1 Rd2 38. Kh2 Kg7
39. c4 b5
7 1.60 -0.21 36. g7 h5 37. Re1 Bf3 38. Bxe5 Rxe5
39. f6 Kf7 40. Bxf3 <HT>
7 1.70 ++ 36. Re1!!
7 1.90 0.45 36. Re1 Bf3 37. Rf1 Ng4 38. Nxg4 Bxg4
39. f6 e3
(2) 7-> 1.98 0.45 36. Re1 Bf3 37. Rf1 Ng4 38. Nxg4 Bxg4
39. f6 e3
8 2.11 0.51 36. Re1 Bf3 37. Rf1 b5 38. Bxe5 Rxe5
39. Bxf3 exf3 40. Rxf3 Kg7
8 3.07 0.61 36. Kg1 h5 37. Bxe5 Rxe5 38. f6 Rd2
39. Re1 Bf3 40. f7+ Kg7
8-> 3.07 0.61 36. Kg1 h5 37. Bxe5 Rxe5 38. f6 Rd2
39. Re1 Bf3 40. f7+ Kg7
9 4.58 0.75 36. Kg1 Rd6 37. Kf2 Bh5 38. Rf1 Rf6
39. Ke1 Kg7 40. Bxe4
9-> 4.73 0.75 36. Kg1 Rd6 37. Kf2 Bh5 38. Rf1 Rf6
39. Ke1 Kg7 40. Bxe4
10 6.90 0.97 36. Kg1 Rd6 37. Re1 Nf3+ 38. Bxf3 Bxf3
39. f6 Ree6 40. Nf5 Rxf6 41. Bxf6 Rxf6
42. Nxh6+
10-> 7.13 0.97 36. Kg1 Rd6 37. Re1 Nf3+ 38. Bxf3 Bxf3
39. f6 Ree6 40. Nf5 Rxf6 41. Bxf6 Rxf6
42. Nxh6+
11 13.96 1.09 36. Kg1 Rd6 37. Kf2 Bh5 38. Bxe5 Rxe5
39. Ke1 b5 40. g4 Bxg6 41. fxg6 Rxg6
11-> 14.33 1.09 36. Kg1 Rd6 37. Kf2 Bh5 38. Bxe5 Rxe5
39. Ke1 b5 40. g4 Bxg6 41. fxg6 Rxg6
12 33.13 1.16 36. Kg1 Bf3 37. Bxf3 exf3 38. Kf2 Rd7
39. Re1 h5 40. Nc4 Ng4+ 41. Kxf3 Rxe1
42. Bxe1 Kg7 43. Bc3+ Nf6 44. Bxf6+
Kxf6
12-> 33.82 1.16 36. Kg1 Bf3 37. Bxf3 exf3 38. Kf2 Rd7
39. Re1 h5 40. Nc4 Ng4+ 41. Kxf3 Rxe1
42. Bxe1 Kg7 43. Bc3+ Nf6 44. Bxf6+
Kxf6
13 1:04 1.39 36. Kg1 h5 37. Kf2 Bg4 38. Re1 Nf3
39. f6 Kf8 40. Rd1 Rxd1 41. Nxd1 Bf5
42. g7+ Kf7 43. Ke3
13-> 1:05 1.39 36. Kg1 h5 37. Kf2 Bg4 38. Re1 Nf3
39. f6 Kf8 40. Rd1 Rxd1 41. Nxd1 Bf5
42. g7+ Kf7 43. Ke3
14 2:14 1.43 36. Kg1 Bf3 37. Bxf3 exf3 38. Kf2 Rc8
39. Rh1 c5 40. Rxh6 cxb4 41. Bxb4 Rc6
42. Rh7 b6 43. Be7 Rc7
14-> 2:19 1.43 36. Kg1 Bf3 37. Bxf3 exf3 38. Kf2 Rc8
39. Rh1 c5 40. Rxh6 cxb4 41. Bxb4 Rc6
42. Rh7 b6 43. Be7 Rc7
Bob
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