Author: Robert Hyatt
Date: 14:32:34 06/26/98
Go up one level in this thread
On June 26, 1998 at 13:42:08, Don Dailey wrote: >Hi Bob, > >I disagree on your disagree : > I double-dog-disagree with your disagree with my disagree. :) I read your post to say that EGTB's were minor additions overall. In my case, they are more than minor, because I play at least 2-3 every day, and most would be draws, rather than wins, without the tablebases. Others are very minor in overall effect, but KRP really sees a lot of action with me. If you didn't say what I thought you said, then I retract my disagree and double-dog-disagree. :) > >>>One more example. Endgame databases are an example of PERFECT >>>knowledge and most databases contain thousands if not millions of >>>terms or parameters or whatever you choose to call them. And yet >>>despite this massive amount of knowledge, they do not contribute more >>>than a few rating points to a chess program. And this is with PERFECT >>>knowledge. Most of the strength they do contribute is concentrated >>>among 2 or 3 common endings. It's a whole lot of knowledge, but >>>rarely used. >>> >> >>I disagree here. KRP vs KR is a big winner. > >I'm not sure what you are disagreeing about. This is one of the >endings that I believe is in the 2 or 3 common ones that should be >covered. > >> I win many pawns, against >>GM's and more particularly against other programs, and many of these games >>end up KRP vs KR where I win when ahead, and draw when behind. A couple >>of weeks ago, Crafty was playing DiepX, and in 4 successive games, 3 were >>won by this endgame database. Because I won a pawn, held on to it, trading >>into a won position at just the right moment. 3 of 4 there. There is hardly >>a day (playing other computers) where I don't see several of these. Against >>humans, no, because they break badly when they break and the game doesn't >>drag on... > >I actually had a suspicion you would write back saying you won a large >percentage of games as a direct result of some database. But instead you >said you won a LOT of games with them. But I need to know what percentage >of games you won. But before you tell me this, I also need to know >how many of these games you would not have won without the database. >This ending can be won by most programs most of the time without the >database. I know this because I once asked Larry to help me cover >this ending with knowledge and we discovered it was not difficult to >do. I'm not saying this is just as good, the database is clearly a >better way to handle this and has the advantage of knowing the >game theoretic results in advance. But what I am saying is that >you do not really know how many games it's actually winning for you. >I don't think you can claim to be winning games left and right because >of this database. > >I don't discount the value of databases at all, I'm for them and we >have a student working on them for Cilkchess. I have to be realistic >though and I don't expect anything more than a few rating points, I >would say even 30 points is wildly optimistic. Think about what >30 rating points really mean. You have to pick up a half point >pretty often to get even 30 rating points. A lot of games never get to >endings, the ones that do usually get to ones that are draws, or >easy wins where no database is needed. Now a small percentage of what >is left over end up in one of our databases but most of these databases >are easy wins (depending on which ones you implement of course) and >the program again doesn't really desparately need them (I don't need rook >vs king.) >The ending BNvsK is hard to win without specific knowledge or a >database but it occurs so rarely that I doubt it's worth more >than a single fraction of a percent in rating. >Finally you get to the interesting endings that occur frequently >compared to other endings (but still not very frequently) where >you must win or draw and it's not completely trivial. Still >most programs will manage to win or draw them. Your example is >a case in point, a little knowledge can win this ending (most >of the time) without needing the database. > >Bob, > >All of my discussion above assumes the current state of the art in >endgame database technology. If it was possible to cover every >single 6 and 7 man database, then I think we would have a real >breakthrough. Programs would suddenly be 40-80 rating points >stronger and opponents would be pressured to avoid simple >endgames and indirectly more complex ones. > >Long live "brute force"!! > > > >>>There will quickly come a point when the bad knowledge that ALL our >>>programs have will place a bound on its possible strength (given a >>>certain amount of hardware.) Learning lots of rare endings and how to >>>play them will help in tiny incremental ways but never make up for the >>>other problems that are more QUALITATIVE. >>> >>>Saying Deep Blue or any other program has a billion parameters in it's >>>evaluation function doesn't say much of anything about how good its >>>evaluation is. >>> >>>Bob makes a strong case that Deep Blue is not limited to simplistic >>>evaluation just because it is implemented in hardware and in fact may >>>contain more terms than any other program. This is great and I'm all >>>for it, wish I had it too. But it's really hard for me to draw the >>>conclusion that it MUST be better because of this. This is an issue >>>that must be considered separately I consider the term count a minor >>>point although not totally irrelevant. (Don't blast me Bob because I'm >>>not saying Deep Blue sucks either, I certainly appreciate the point >>>you are making with Vincent that hardware evaluation does not equal >>>STUPID program.) >> >> >><blaster holstered> :) >> >>I have no idea of a way to prove that a bigger eval is better, but I'd >>certainly bet that it is no worse, unless it's written by dummies of >>course... > >My point exactly. I don't have a problem with more and more knowledge, >I'm just saying the real problem is in the engineering of this >knowledge. I think the bottleneck is this. > > >- Don
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.