Author: Marc van Hal
Date: 07:50:06 05/09/02
Go up one level in this thread
On May 08, 2002 at 12:15:11, Christophe Theron wrote: >On May 08, 2002 at 04:19:16, Amir Ban wrote: > >>On May 07, 2002 at 13:35:12, Christophe Theron wrote: >> >>>On May 07, 2002 at 07:44:16, Amir Ban wrote: >>> >>>>On May 06, 2002 at 18:06:47, Christophe Theron wrote: >>>> >>>>>On May 06, 2002 at 15:34:01, Amir Ban wrote: >>>>> >>>>>>On May 05, 2002 at 19:58:09, Christophe Theron wrote: >>>>>> >>>>>>> >>>>>>>"Knowledge" in the sense of positional evaluation (that's what most people think >>>>>>>about when they talk about knowledge) makes for 10% of the strength of a chess >>>>>>>program. >>>>>>> >>>>>>>Chess is 90% about tactics (which is a concept close to "search"). >>>>>>> >>>>>> >>>>>>Before strongly disagreeing (as I guess I will), what does this mean ? >>>>>> >>>>>>If I freeze my search engine and work only to improve the evaluation, how much >>>>>>do you expect the total strength to improve ? Is it limited ? >>>>> >>>>> >>>>>I expect the strength of your engine to improve, but not much in regard to the >>>>>energy invested. Because you are going to focus your efforts on an area that >>>>>does not have the biggest potential in strength. >>>>> >>>>>On the other hand people will love it more and more because it will have a much >>>>>better playing style. >>>>> >>>>>People can forgive gross tactical blunders, but not slight positional mistakes. >>>>>Go figure... >>>>> >>>>>Here I'm talking about current top engines of today, naturally. >>>>> >>>>>Building a chess engine with a broken evaluation to demonstrate that a better >>>>>evaluation could improve it tremendously is not in the spirit of my idea. >>>>> >>>>> >>>>> >>>>>>I understand that you are saying that it will change the style but overall >>>>>>strength will not be much changed. >>>>> >>>>> >>>>>I do not know exactly how far we will be able to go with the 10% I attribute to >>>>>positional evaluation. >>>>> >>>>>I'm not saying it counts for nothing and that overall strength will not benefit >>>>>from research in this area. >>>>> >>>>>I believe that the positional evaluation is the part of a chess program >>>>>responsible for only 10% of the strength, and that the rest is done by the >>>>>search. >>>>> >>>>>I believe that the positional evaluation is responsible for most of what people >>>>>perceive as the "playing style". >>>>> >>>>>Now you can strongly disagree, I do not have the absolute truth. >>>>> >>>> >>>>Ok. I think this is wrong. Anyway I'm working for a long time under the >>>>assumption that it's the evaluation rather than the search that needs work. >>>> >>>>The search engine of Junior7 is basically the same as Junior6. >>>> >>>>Junior5 was the last engine where I did extensive work on the search. Since then >>>>in terms of effort it was at least 80% evaluation, no more than 20% search. >>>> >>>>Amir >>> >>> >>> >>>Then your work is a real success. That makes a lot of elo points gained from >>>working almost exclusively on the evaluation. >>> >>>How much in your opinion? As Junior 7 is 93 elo points stronger than Junior 5 on >>>K6-450 (with the usual error margin, of course), how much would you say come >>>from your work on the evaluation? 60? 70? 80?? >>> >> >>Something like that. I don't invest in measuring accurate rating differences, so >>I certainly don't know how to break it down. >> >> >>>I wouldn't have believed that it is possible, but obviously it is. >>> >>>I guess that the fact that you have a strong chess player in the team has an >>>influence on the choice to work more on the evaluation, right? >>> >> >>Not really. I don't code to advice by Boris. The language of GM's and computer >>language is too far apart. I usually can't translate what I understand into code >>lines, although occasionally I can. > > >I understand you perfectly. I have exactly the same problem when I receive >advices from strong chess players. > >Jeroen is however the best in this. When he gives an advice, he tries to >translate it into something that is closer to the machine understanding than any >other strong player I know. > >But it still takes me ages to implement correctly Jeroen's good advices. > >It's hard to mess with the evaluation without breaking something. > > > >>Boris has indirect influence, through pointing out patterns of failure and >>assessment of progress. There was one event that had a lot of influence on my >>course. It was during the Dortmund tournament (July 2000) he told us towards the >>tournament that he now understands how to play against Junior. We played several >>10' blitz games on my laptop in a hotel room, and to my amazement he showed how >>in a quite offhand way he can beat Junior (this was an improved J6) almost every >>time. From watching the games, I understood that there's no way to deal with >>that through search. > > >So it must be the reason why newer versions of Junior are considered more >"speculative"? If it can't be solved by search, evaluation has to do it. > > > > Christophe To my point of vieuw the treuth lays in the midle Which basicly is demonstrated by Junior7 It many times finds draws where an other program still thinks it has an advantage. In the otherway Junior7 also does not want to play torwards an endgame (While this would have been easely winning) for the same reason Not to mention that I found out that increased kingsafety can be a real pain for a programs. The oldest programs already had problems with a move like f4 because then a bischop or Queen can give a check on c5 This is still not solved For this reason Chessmaster still will not likely play this move just set up the position with a pawn on f4 and a pawn on h3 Most programs don't like such a position after White has castled Kingside. and especialy not if it calcultes a check black might give Which does not only ends up for a pain for the program but also for the one who might want to use it for analyses. many times you then see an evaluation of -1.23 or something which ends up with -a +2.00 score 5 moves later Evaluation of kingsafety positions might help So the checks will be seen as a check and not as something which by all means has to be stopped. Or in human terms if you are a good attacker you also need to be a good defender. You also can find this out after revieuwing the games from Alekhine and other attacking players. Many times the program will give the attacking player temporerly a negative score and does not find an improvement over the moves played in the game. It is more easy to find the moves on evaluation then on search. This only can change if you find out a deeper search methode So it will not get a headegg banging against the horizon when it is used on a fast machine. Regards Marc van Hal
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