Author: Robert Hyatt
Date: 10:31:11 10/01/01
Go up one level in this thread
On October 01, 2001 at 12:53:09, Uri Blass wrote: >On October 01, 2001 at 12:37:09, José Carlos wrote: > >>On October 01, 2001 at 12:30:44, Uri Blass wrote: >> >>>On October 01, 2001 at 12:11:51, Robert Hyatt wrote: >>> >>>>On September 30, 2001 at 11:12:47, Uri Blass wrote: >>>> >>>>>On September 30, 2001 at 10:39:50, Miguel A. Ballicora wrote: >>>>> >>>>>>On September 30, 2001 at 06:15:44, José Carlos wrote: >>>>>> >>>>>>>On September 29, 2001 at 20:15:16, Gareth McCaughan wrote: >>>>>>> >>>>>>>>José Carlos wrote: >>>>>>>> >>>>>>>>> The point is not the move, but the eval. The program must >>>>>>>>> know white is winning: >>>>>>>>> >>>>>>>>> [D]R4rk1/5pp1/5q1p/1p1Qp3/8/1B6/1PP2bPP/5K2 w - - 0 1 >>>>>>>>> >>>>>>>>> Qxf7+ and after the changes, the pawn ending is won. >>>>>>>> >>>>>>>>Crafty 18.11, Athlon 1GHz, has +0.8 after 0.4 seconds (8 ply), >>>>>>>>rising to 0.93 after 11 seconds, 1.17 after 28 seconds, 1.36 >>>>>>>>after 6 minutes. It plays Qxf7+ at all depths. >>>>>>>> >>>>>>>>-- >>>>>>>>g >>>>>>> >>>>>>> It doesn't surprise me at all. Crafty is probably the best in the world >>>>>>>evaluatiing pawn endgames. >>>>>>> >>>>>>> José C. >>>>>> >>>>>>Anyway, the position "as is" is not perfect for a test because white will want >>>>>>to play Qxf7 even if doesn't understand the upcoming pawn endgame (because Qxf7 >>>>>>just win a pawn). >>>>> >>>>>No >>>>> >>>>>Junior7 prefers to force a draw by perpetual check and >>>>>cannot find Qxf7. >>>>> >>>>>If a program believes that black is better in the pawn endgame >>>>>then it is not going to find Qxf7. >>>> >>>>If a program believes black is better in that position after the trades, >>>>then it already has a serious endgame problem (lack of knowledge). Nothing >>>>else matters in such cases... >>>> >>>> >>>>> >>>>> >>>>> What is very good is the idea, so I try to improve the >>>>>>original position in a way that the first move gives an idea that the program >>>>>>understand the endgame. >>>>>> >>>>>>[D]8/4k1p1/1p2B2p/4p3/8/4P2P/1PP1KbP1/8 b - - am Bxe3; >>>>>> >>>>>>Crafty 17.14 avoids Bxe3 in an instant without any problem even in my K6-II 400 >>>>>>mhz. How about other programs? The test is simple but I like it in the modified >>>>>>version because it tells me fi a program understand a couple of concepts. >>>>>>For instance, Gaviota wants to play Bxe3, So I know what to modify :-). >>>>>> >>>>>>Regards, >>>>>>Miguel >>>>> >>>>>Deep Fritz also likes Bxe3 >>>>>New position >>>>>8/4k1p1/1p2B2p/4p3/8/4P2P/1PP1KbP1/8 b - - 0 1 >>>>> >>>>>Analysis by Deep Fritz: >>>>> >>>>>1...Kxe6-- >>>>> ± (1.19) Depth: 1/3 00:00:00 >>>>>1...Kxe6-- >>>>> ± (1.19) Depth: 1/3 00:00:00 >>>>>1...Bxe3! >>>>> ² (0.44) Depth: 1/4 00:00:00 >>>>>1...Bxe3! >>>>> = (-0.13) Depth: 1/4 00:00:00 >>>>>1...Bxe3 2.Bd5 >>>>> = (-0.13) Depth: 2/5 00:00:00 >>>>>1...Bxe3 2.Bd5 Kd6 >>>>> = (-0.16) Depth: 3/6 00:00:00 >>>>>1...Bxe3 2.Bf5 Kf6 3.Be4 >>>>> = (-0.06) Depth: 4/7 00:00:00 >>>>>1...Bxe3 2.Bd5 Kd6 3.c4 Bd4 >>>>> = (-0.06) Depth: 5/8 00:00:00 1kN >>>>>1...Bxe3 2.Bd5 Bc5 3.g3 g6 4.c4 >>>>> = (-0.03) Depth: 6/10 00:00:00 3kN >>>>>1...Bxe3 2.Bd5 Bc5 3.g3 g6 4.Be4 Kf6 >>>>> = (-0.03) Depth: 7/11 00:00:00 7kN >>>>>1...Bxe3 2.Bd5 Bc5 3.g3 g6 4.Be4 Kf6 5.c3 >>>>> = (0.00) Depth: 8/12 00:00:00 16kN >>>>>1...Bxe3 2.Bf5 Bc1 3.b4 Bb2 4.c4 Ba3 5.Be4 >>>>> = (0.03) Depth: 9/15 00:00:00 50kN >>>>>1...Bxe3 2.Bd5 Kd6 3.Be4 Bf4 4.b4 b5 5.Bd3 Kc6 6.c4 bxc4 >>>>> = (0.09) Depth: 10/15 00:00:00 99kN >>>>>1...Bxe3 2.Bf5 Bc1 3.b3 Bf4 4.Be4 Kd6 5.c4 Kc5 >>>>> = (0.09) Depth: 11/17 00:00:00 231kN >>>>>1...Bxe3 2.Bf5 Bc1 3.b3 Bf4 4.Be4 Kd6 5.b4 h5 6.g4 hxg4 7.hxg4 >>>>> = (0.09) Depth: 12/19 00:00:01 483kN >>>>>1...Bxe3 2.Kxe3 Kxe6 3.c4 h5 4.g4 g6 5.b4 h4 6.Ke4 g5 7.c5 >>>>> = (0.19) Depth: 13/21 00:00:02 1039kN >>>>>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.Ke4 h5 5.h4 >>>>> = (0.25) Depth: 14/22 00:00:03 1611kN >>>>>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.Ke4 Ke6 5.b3 h5 6.h4 >>>>> = (0.25) Depth: 15/23 00:00:06 3076kN, tb=1 >>>>>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.b4 Ke6 5.Ke4 >>>>> ² (0.41) Depth: 16/24 00:00:12 5395kN, tb=6 >>>>>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.b4 h5 5.g4 hxg4 6.hxg4 Kd7 7.Ke4 >>>>> ² (0.50) Depth: 17/25 00:00:25 11346kN, tb=50 >>>>>1...Bxe3 2.Kxe3 Kxe6 3.c4 Kd6 4.b4 h5 5.Ke4 Ke6 6.h4 Kd6 7.c5+ >>>>> ² (0.56) Depth: 18/27 00:00:47 21088kN, tb=198 >>>>>1...Bxe3 2.Kxe3 Kxe6 3.c4 h5 4.h4 Kf5 5.b4 Ke6 6.Ke4 Kf6 7.c5 >>>>> ² (0.59) Depth: 19/30 00:01:54 49750kN, tb=993 >>>>> >>>>>(Blass, Tel-aviv 30.09.2001) >>>>> >>>>>Note that finding Kxe3 is also not an easy problem >>>>>for part of the programs >>>>> >>>>>Deep Fritz has no problem but Junior7 cannot find it >>>>> >>>>>I remember that I told Amir Ban some years ago about >>>>>pawn endgames problems and he told me that it is not important >>>>>because Junior almost never does not get pawn endgames >>>>>so it is more important for him to work about other problems >>>>>in the evaluation. >>>> >>>>:) >>>> >>>>Funny comment. Which will change after playing a lot of GM players. :) >>> >>>I am not sure about it. >>> >>>I remmeber that Junior4.9 drew against 3 GM's at tournament time control >>>at that time(1998 if I remember correctly). >>> >>>No game was pawn endgame at that time >>> >>>I also do not remember pawn endgames from the tournament in durtmond when Junior >>>got 4.5 out of 9 against GM's so I doubt if GM's can practically often take >>>advantage of the weakness of Junior. >>> >>>I did not watch GM's play against Junior in ICC but having a weakness does not >>>mean that the GM's can often take advantage of it and the only proof is in games >>>against Junior and not games against Crafty. >>> >>>Uri >> >> I believe Bob didn't mean 3 or 9 games, but hundreds. Let Junior play a lot of >>games against GM's at ICC and, if it still has that weakness, they'll sure >>discover it and win game after game. In 12 games against different players, the >>cannot discover such a weakness, so it's not relevant. >> >> José C. > >I read that Slater claimed that Junior is good against humans >See http://www.icdchess.com/forums/1/message.shtml?191120 > >It seems that it is not simple to take advantage of Junior's weaknesses. > >The GM's who played against Junior also could train at home against the >commercial Junior,so the claim that they could not discover the weakness does >not convince me. > >Uri So? I _could_ practice at home, dodging bullets from a 44 magnum, before I engage in a duel with someone that will use one. But since I really don't intend on engaging in such a duel, then I am probably not going to practice for it. The point is, if a programmer says "I am going to ignore the endgame because I never intend to reach one" that is a ridiculous position to take. Do you _really_ believe that a computer can beat a GM in tactics game after game? Even if the GM intentionally tries to reach even endgames where he knows that the program's inferior knowledge will let it down badly? I have taken the path that says "OK, human GM, if you want to go for an endgame, you had _better_ know what you are doing. I am not a dummy. I know how to play the ending as well as I know how to play the middlegame. So don't try to trade into inferior endgame positions and swindle me. It won't work." Ask GM Mecking about Crafty in the endgame. He has played it _many_ times and reached them. And he loses most of them. Or at least he loses as many in the endgame as he does in the middlegame. It used to be different. But I grew tired of watching simple losses happen when the program couldn't win tactically and ended up in an endgame that it should have won, but couldn't because it didn't know enough to do so. Ask a group of programmers "How many of you would prefer to see your program playing in a middlegame if at all possible, rather than in an endgame?" I'd expect everyone to raise their hand. Probably me included. But ask "How many of you would rather give positional concessions to stay in a middlegame rather than trading into an advantagous endgame?" And most would now sit on their hands, knowing that the endgame is a problem. I'm perfectly happy to see Crafty in a king + pawn + minor piece or two ending. Or even a king and pawn ending. Because it has a good feel for what to do. It isn't perfect. But it isn't lousy either. Not when it can play endings against top GM players and win "won" positions and not lose won/drawn positions very often at all.
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