Author: Kolss
Date: 12:24:24 01/11/03
Go up one level in this thread
On January 11, 2003 at 14:01:28, Robert Hyatt wrote: >On January 11, 2003 at 12:46:35, Kolss wrote: > >>On January 11, 2003 at 11:14:10, Robert Hyatt wrote: >> >>>On January 11, 2003 at 07:43:24, Drexel,Michael wrote: >>> >>>>[D] 4nnk1/8/6b1/4BP2/2N1B1K1/8/8/8 b - - 0 1 >>>> >>>>I just came over this endgame position with Crafty 19.01 as analysis engine in >>>>CB-GUI. Crafty suggested 1...Bxf5+ with a score of 0.01. >>>>1...Bf7 seems to be a simple draw. >>>>you probably told him 3 pieces against 2 pieces without pawns is draw, but I >>>>doubt this is a good idea in the endgame BBNK vs. NNK. You might be better >>>>informed but I would think this endgame is almost always a win and would even >>>>assume that it is almost always a win within 50 moves. >>>>If I were a tablebase-expert like you, I would fix it immediatly, whether it is >>>>important or not. >>>> >>>> >>>>In games against Fritz 8 Crafty will resign in not more than 8 moves: >>>> >>>>[Event "ATHLONXP"] >>>>[Site "ATHLONXP"] >>>>[Date "2003.01.5"] >>>>[Round "1"] >>>>[White "Fritz 8"] >>>>[Black "Crafty 19.01"] >>>>[Result "1-0"] >>>>[SetUp "1"] >>>>[FEN "4nnk1/8/6b1/4BP2/2N1B1K1/8/8/8 b - - 0 1"] >>>>[PlyCount "14"] >>>> >>>>1... Bxf5+ 2. Bxf5 Ng7 3. Be4 Nge6 4. Kf5 Kf7 5. Bd5 Ke7 6. Bd6+ Kd7 7. Ke5 >>>>Ng6+ 8. Kf6 1-0 >>> >>>First, Crafty well knows that KBB vs KN is a win. But it isn't seeing that >>>here until way deep into the search. In 99.999999999999% of these endgames >>>with 3 minors vs 2 minors, the game is a draw. Handling that one special case >>>here and there is not going to make it play better, and would almost certainly >>>hurt it overall as it really should say KBBN vs KNN is a draw in almost all >>>cases. >> >>I do not agree. IMHO, the stronger side should win in most cases. Especially if >>you score all positions as 0.01, you will allow the opponent to make progress, >>drive your king into a corner and seperate the knights. >> >>Regards, Munjong. > > >Do not agree with what? That king + 3 minors vs king + 2 minors is almost >always a draw? or that KBBN vs KNN is mostly drawn? I'd be willing to wager >that _most_ of the above positions are dead draws. Of course, I accept and respect your opinion in this regard. Nonetheless, allow me do differ: I suppose that most positions KBBN vs. KNN are won for the stronger side. In fact, I would not be surprised if in a couple of years, a properly working chess program which uses endgame databases (TB) announced forced checkmate for white after 1. ... Bxf5??. I can probably agree that king + 3 minors vs. king + 2 minors is mostly a draw IF the stronger side is not up more than one minor in material, whereas the bishop is scored higher than the knight (B > N), such that 2B - N > B = highest value for minor. In fact, I believe that this is a pretty good rule for most pawnless endings. E.g. RB vs. R is very drawish, QB vs. Q or QN vs. Q are extremely drawish, RBB vs. RN offers good winning chances for the stronger side. This is of course only my own, subjective view of the matter. >Note that I don't score them as "drawn". I score them as "side with most >material can't win" which is different... The end result is very similar. If you score all such positions with at most 0.01 (actually, Crafty 19.01 always says 0.00 on my machine - please pardon me if I do not have the most recent version to check) for the stronger side, your program will most likely lose to any program which tries to make progress, even if yours outsearches the other program by 4 (number picked at random) plies. Regards, Munjong.
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.