Author: Gian-Carlo Pascutto
Date: 14:46:42 12/25/99
Go up one level in this thread
On December 25, 1999 at 13:27:45, John Hendrikx wrote: >I've tried adding null-moves as well, but haven't been very succesful. I >need some more to go on before I can get it right, but I can't find good >examples or descriptions of them. So far what I've tried is to try a >null-move before doing any real moves at a certain level of the tree, and >searching the null-move to the same depth as usual; Erm, this basically defeats the idea of a nullmove search: to get a cutoff with *less* work. >my problem is that I >don't know what to do with the returned score. From what I gathered one >should create a cut-off when the score is 'not so good' even while doing >two moves in a row.. I prefer to reverse this: when the other side is allowed to move twice and a shallow search yields a score for us that is still enough for a beta cutoff, we are quite certain we'd have gotten a beta cutoff if we did a full-depth search. >it didn't work for me though. It was far slower (1.5 >times) with the same results, and only a few dozen null-move cutoffs at >6 plies orso. You should be getting over 50%. (at least, that the number I get) >Should null-moves be tried for both black and white? Your search shouldn't make any distinction between black and white. Using a negamax-type search will make your program a lot less complicated. >> >>1. hash table move > >Is that the same as the Principle Variation? > No...there is only one principle variation, but all positions have a best move. -- GCP
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.