Author: Sune Fischer
Date: 15:30:26 07/29/04
Go up one level in this thread
On July 29, 2004 at 11:44:39, Robert Hyatt wrote: >"more complicated" != "more advanced". I don't believe it is possible to >accurately forecast the time for the next iteration. Which means when is it >appropriate to do that quick nullwindow search? I can't pridict when a check extension is wasted and when it is useful either, I can only say if it works better or worse on average. > And when you do it and it >returns way quicker than you expected, what do you do with the remaining time? > >There appear to be more problems this way than with what I currently do... Simple != Good (I can play that game too:) >>But you have not tested what I'm suggesting. > >I have definitely tested doing a fail-low search. You can find references to >that back in 1978 which was when I finally dumped the idea of "don't start the >next iteration if I don't believe it can be finished..." Then why did it not work, which part failed, what is your analysis? >> >>>Your "assumption" is based on facts that have tons of contradictory evidence (IE >>>I _have_ done lots of testing and reported on it many times in various ways.) >> >>AFAIK it was a completely new spin on an old idea. > >There's nothing new about the null-window search at all. As I said, in 1980 >_every_ search I did started with a null-window search. As did Belle's... Don't mix two experiments here, I'm not talking about starting every search with a nullwindow... Be careful with drawing too many parallels here. > >> >>I read your conclusion that ply N took 1.5 and ply N+1 took 1.4. >>This is what I call the same magnitude, ie 1.4 >> 0.15*1.5 > >Yes. But _both_ together took less than 15% of the total time used up to that >point... Yes that's true, but I think you should compare the last iteration time with the time remaining, that way you eliminate a big branchfactor issue. Secondly, don't jump to the conclusion that it won't work because you found a position where it might not work perfectly. I can show you 100 positions where nullmove causes more damage then good, still that doesn't mean you should turn it off in Crafty, right? :) I think only testing is the way to go. >>I don't think it varies "too" much. >> >>-S. > > >You are lucky. Mine is wildly varying... Hehe, but on average.... :) -S.
This page took 0.01 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.