Author: Amir Ban
Date: 15:25:49 06/23/98
Go up one level in this thread
On June 23, 1998 at 16:19:32, Bruce Moreland wrote: > >On June 23, 1998 at 09:45:45, Moritz Berger wrote: > > >>I took the example position on Eds page to test the 'anti GM' qualitities of >>some other programs (P233MMX, NT 4.0, 128 MB RAM). Especially Junior's >>performance is frightening (Rxe6 at 4.5 ply after 2", after 4" even with >>positive evaluation!). >> >>No question that Anti-GM-Rebel is now among the very best programs in this >>position, so Ed clearly is on the right track ... > >>2rqk2r/pb1nbp1p/4p1p1/1B1n4/Np1N4/7Q/PP3PPP/R1B1R1K1 w k - 0 1 > >>Junior 4.6 32768 KB hash tables >>00:04 9 semiply 0.04 Rxe6! >> >>Fritz 5.01 98304 KB hash tables >>00:04 7/28 -1.13 Rxe6! > >>Hiarcs 6 (Fritz engine) 98304 KB hash tables >>01:42 7/23 -0.88 Rxe6! > >>Crafty v15.14, hash table memory = 48M bytes, pawn hash table memory = 10M > >> 9 3:49 ++ 1. Rxe6!! > >>Shredder 2.0 > >> 9.07 5:24.71 -0.15++ Rxe6 (17.259.985) > >Ferret: > >Never, I hope. > >I get a fail high a few minutes into this, but the re-search fails low. > >I like aggressive play, and I like speculative play that works, but I think that >programs are seeing something here that doesn't exist. > >Crafty likes the position after Rxe6, it ends up with a positive score. Bob >wasn't around so I could ask him, but I did some experiments and got permission >retroactively. > >I set up the position after Rxe6 fxe6 and asked Crafty to play white (30 0, with >Crafty on a 4 processor P6/200 and mine on a 533 mhz Alpha). It was happy for a >couple of moves then the bottom fell out. It tried to throw more fuel on the >fire and ended up a rook down with nothing to show for it. > >I reversed the colors and tried again, and mine started out at like -1.7 and >stuck there into an ending where it as down the exchange for a pawn, and had >worse development. > >I am hoping that the reason my program won't play this is that it sees that the >bottom falls out. > >I would be happy to be shown a line that has any promise for white. If someone >thinks that this really does win, or at least offers good counterplay, please >post a line. > The critical line is: 1.Rxe6 fxe6 2.Nxe6 Qa5 3.Bxd7+ Kxd7! 4.Nc5+ Ke8 5.Qd7+ Kf7 6.Nxb7 Rc7 7.Nd6+ Kg7 8.Ne8+ Rxe8 9.Qxe8 Nf6! The rook sac is not at all speculative. It's just wrong. Your eval should be a significant plus for white at at least two points in it, but this doesn't hold because black has these counter-resources. Black has only one defense, but it works. The hard part for black is seeing 3...Kxd7. 3...Kf7 is a dead loss. >My own analysis shows a nasty check or two, then black is simply up material. > No, there's more to it as you can see in the line. I don't understand how your program can dismiss this line without passing through intermediate depths where it would think it works. >Additionally, I would like to ask those who report when they find this move to >see how long their programs hold the move. Do they stick with it for 24 hours? > It takes me 7 minutes on P-II 300 to play 1... fxe6. Amir
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