Author: Keith Ian Price
Date: 22:45:21 01/15/06
Go up one level in this thread
On January 16, 2006 at 01:32:48, Uri Blass wrote: >On January 16, 2006 at 01:18:14, Keith Ian Price wrote: > >>On January 16, 2006 at 00:57:35, Uri Blass wrote: >> >>>The reason is simple. >>>It is known that many programs simply evaluate repetition as a draw and rybka is >>>one of them(many programs are going to see a draw in the same conditions). >>> >>>It is the simple solution to the problem of avoiding repetitions. >>> >>>programs of course can evaluate only 3 time repetition as a draw but it may >>>cause them to search bigger trees for no good reason so it is not clear if it is >>>better for playing strength. >>> >>>programs that evaluate first repetition not as a draw may waste time by allowing >>>repetitions and in some cases it even may cause draw by the 50 move rule because >>>in superior position they may not be able to be lucky to find the right plan on >>>time when avoiding repetition may force them to find the right plan if they >>>evaluate first repetition as a draw. >>> >>>I choose to evaluate first repetition as a draw because when I have 2 options >>>when it is not clear which one is better I prefer the simpler option. >>> >>>Uri >> >>Well, I thought that might be the case, but why does the 32-bit version evaluate >>it as losing, while the 64-bit version thinks it's a draw. And should the >>program evaluate a non-forced repetition as a draw, if it is so far behind? >> >>kp > >I do not know Rybka 1.0 beta 32-bit see a draw when it get the game and not >losing score for black. >Maybe latest 32 bit version is different. > >Deep Shredder 9.02 x64 - Rybka 1.0 Beta, Blitz:16' 2005 >b1r1qn1k/1rb3p1/2p1p2p/2N1P3/1P1P4/R2B1N2/3Q1PPP/2R3K1 b - - 0 1 > >Analysis by Rybka 1.0 Beta 32-bit: > >43...Rbb8 > = (0.00) Depth: 3 00:00:00 >43...Rbb8 > = (0.00) Depth: 4 00:00:00 >43...Rbb8 > = (0.00) Depth: 5 00:00:00 >43...Rbb8 > = (0.00) Depth: 6 00:00:00 >43...Rbb8 > = (0.00) Depth: 7 00:00:00 >43...Rbb8 > = (0.00) Depth: 8 00:00:00 1kN >43...Rbb8 > = (0.00) Depth: 9 00:00:00 1kN >43...Rbb8 > = (0.00) Depth: 10 00:00:00 2kN >43...Rbb8 > = (0.00) Depth: 11 00:00:00 3kN >43...Rbb8 > = (0.00) Depth: 12 00:00:00 7kN >43...Rbb8 > = (0.00) Depth: 13 00:00:01 12kN >43...Rbb8 > = (0.00) Depth: 14 00:00:01 18kN >43...Rbb8 > = (0.00) Depth: 15 00:00:01 28kN >43...Rbb8 > = (0.00) Depth: 16 00:00:02 48kN >43...Rbb8 > = (0.00) Depth: 17 00:00:03 85kN >43...Rbb8 > = (0.00) Depth: 18 00:00:04 148kN >43...Rbb8 > = (0.00) Depth: 19 00:00:05 250kN >43...Rbb8 > = (0.00) Depth: 20 00:00:06 402kN > >(, 16.01.2006) > >Uri Ok. The difference between Chris' eval, and yours is that you loaded the whole game, so that it could see the repetition. I still think with a score of 2.72, it should not assume that the other side will take the repetition. It might have found a better answer that would lower the score to 1.5 or so, but rejected it for the 0.00 false score it came up with. thanks for the answers, kp
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