Author: Uri Blass
Date: 00:51:08 10/11/02
Go up one level in this thread
On October 10, 2002 at 20:09:12, Robert Hyatt wrote: >On October 10, 2002 at 16:59:54, Jeremiah Penery wrote: > >>On October 10, 2002 at 15:55:32, Uri Blass wrote: >> >>>Deep blue did not see Qe3 in the main line based on the logfiles of IBM. >>>A lot of programs of today can see it with no problem. >>> >>>Some programs can even see the move Kh1 instead of Kf1 of Deep blue(I did not >>>check the last deep Fritz but previous Deep Fritz is one of them). >>> >>>It is not a proof that deep blue is weaker but it is an evidence that Deep >>>blue's evaluation is inferior. >>> >>>Good evaluation is not about knowing the truth(that you cannot know) but about >>>giving a better estimate and it seems that the top programs of today get better >>>decisions based on positional reasons. >> >>In Hsu's book, there is a large section about the 1997 match, going through >>game-by-game. It's very surprising how many evaluation bugs they found, and >>there's no doubt there were many more. The full DB2 never played a serious game >>before the 1997 match, either, so it's inevitable that things weren't tuned to >>the best possible accuracy. It's hard to compare something like that to a >>commercial program of today, which plays thousands of testing games and the >>programmers have as long as they want to tune each parameter. >> >>DB2 only played 6 games in its lifetime. To compare its positional strength to >>anything based on those games is meaningless. Or if you really want, I can >>easily find 6 games where some commercial program was completely clueless >>positionally. :) > > >It simply shows that DB was very resiliant _and_ strong. The fact that the deep blue team found many evaluation bugs in the match against kasparov does not show that it was strong. Deeper blue was clearly the best computer at the time of the match against kasparov. I believe that it could continue to be the best in case that they continue to work on it but kasparov simply destoyed it by losing against it. I believe that bugs in the evaluation are more important in long time control. In blitz you can compensate for wrong evaluation by taking advantage of a tactical mistake. In long time control if you go for a bad position because of a bug there is bigger probability that nothing is going to help you and even if you see that you lose before the opponent see the win you still lose the game. It was barely put >together in time >for the match, yet it managed to win. I did _exactly_ the same thing in 1983 >when we won >the WCCC event. We had not played a complete game prior to round 1. In fact, >as I drove >to New York, Harry Nelson was in Minneapolis at Cray headquarters helping them >fix a >multiprocessing bug in their operating system we had found. We started round 1 >never >having played more than 2-3 moves in a row. And the program performed >flawlessly for >five rounds and won outright... > >DB was very strong, regardless of what others say. To say Fritz is stronger is >a joke, and >a bad one at that. Based on what? DB _did_ beat Kasparov. Fritz is getting >squeezed beyond >imagining. You know that this does not prove nothing because the conditions for the match Fritz-Kramnik are unfair. > I think that the DB accomplishment was remarkable, and all the more >so after >reading Hsu's book which accounts for the year prior to "the match" in 1997. I agree that it was a good result. I have one question about the depth. You say that 12 plies with no pruning in 3 minutes is impossible for Fritz(p850) in normal middle game position(I agree about it). Do you think that 12 plies in software(no pruning in software) and 6 additional plies in hardware in 3 minutes was possible for deep blue. Even if I assume branching factor of 3 to get the last 6 plies then it means that the number of nodes is only 729 times bigger. Deep blue is clearly faster than P850 but the number of nodes is less than 729 times bigger (Fritz get some hundreds of knodes per second on p850). Uri
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.