Author: Otello Gnaramori
Date: 01:04:29 04/06/02
Go up one level in this thread
On April 06, 2002 at 01:52:18, Russell Reagan wrote: >I was sitting around the house tonight thinking about computer chess, as often >happens, and I began to think about why certain programs are better than others. >I began by thinking that most programs use *basically* the same algorithms, with >their own small tweaks here and there. So on equal hardware, some programs might >get a few extra NPS here and there, but it doesn't seem like one program would >be able to gain a significant advantage over another strong program from out >searching it. I would guess that everyone uses some form of alpha-beta or >"enhanced" alpha-beta like PVS, null move, transposition table, and so on...all >the basics that anyone with a strong program knows about. > >So we all know the basic algorithms and hueristics, and yet we still have wide >ranges in program strength. > >This led me to ponder three possible reasons for this, which I will present in >the form of questions to you. > >Do the top programs make use of some methods that the general computer chess >hobbyist does not know about? Any "secrets", or any significant improvements >upon a well known technique? Yes, of course...and they are well guarded secret and they are results from years of research as e.g. Christophe told us once in a thread here. >Secondly, what is the margin of difference that actually makes a difference? For >example, if program A is optimized to the hilt, gaining a few thousand NPS over >program B (or even more), is that really worth anything in terms of playing >strength? Maybe a +0.05 pawns for program A or some equally trivial "advantage", >or is it? Basically, how much better/faster/deeper does the program have to >search to gain a realistic advantage over another program? Small advantages in >speed due to one program being more optimized than another, IMO, would not be >enough to make one program significantly stronger than another. Maybe a half a >point out of many many games. But then again others here would probably know >better than I, so speak up :) I think that NPS is important but not prevailing in strength considerations, more important IMHO are the search algorithm and evals. > >Last, and possibly the most obvious of my possible reasons for this, is to >wonder if the strength differences in programs lie in the most mysterious part >of any chess program, the evaluation function. This seems to be the area where >there is little or no standardization of algorithms, and also the area allowing >for the most creativity. So do we have a winner...the evaluation function? > Not only the eval , but surely also. I'd consider very much the selective search and forward pruning techniques. >Still on the topic of the evaluation function, there are two possible reasons >for evaluation functions causing differences in playing strength. As I see it, >you could have a better evaluation function, leading to a stronger program. >that's option one. Option two, you could have very similar evaluation functions, >but one is highly optimized and executes much faster than another, leading to a >stronger program. > >And of course, if anyone else has any other ideas I'd love to hear them. I don't >ask for any specifics from anyone if you've got some "secret" method that makes >your program significantly stronger (but you are more than welcome to tell us >;), but I'd be very interested in learning that there are more secrets out there >to be discovered. > >Seems like an interesting topic to me. Perhaps determining the key point in this >large battleground we fight upon is the key that determines a world class >commercial program from a good amateur program. Sorry Russell, but that secrets are "trade secret" , don't think you can obtain that advanced infos here :) w.b.r. Otello > >Russell
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.