Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Null move idea

Author: Sergei S. Markoff

Date: 21:47:14 09/25/04

Go up one level in this thread


>I would be unsure about possibly returning incorrect score >= beta in the
> first stage.

Sometimes it happens because of the change of values of the root bounds. In a
root we have (in classic scheme of course) exact score for the best move. Near
the zugzwang positions happens one thing. Some move fails high because of
null-move cutoff. And we doing re-search with more wide window. In this case the
zugzwang will be avoided using method, inroduced by me.

>will not work well with score <= beta logic, whatever beta may be.  Also depth
>differences in nodes vastly affect the score, whether null move or not.

The depth diffenences will be in most cases compensated by window width between
null move score and best move score. Anyway the error will be only if a score
delta is not in a bounds of this window + root aspiration window. Is it need to
explain this? Is the case too often? We need experiments.



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.