Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: null move efficiency

Author: Daniel Shawul

Date: 23:52:12 04/20/04

Go up one level in this thread


On April 19, 2004 at 20:38:47, Mike Siler wrote:

>My program tries a null move search if
>
>1. it's not the endgame
>2. it's not a PV node
>3. it didn't just make a null move
>4. it's not in check and wasn't in check on the previous ply
>5. the remaining depth isn't so small that the reduced depth would take it into
>the qsearch
>
>In general, only around 65% of the null move searches my program performs result
>in a cut-off. Is this normal or do other programs tend to do better (and how)?
>According to Ed Schröder's page, Rebel gets around 93-95%. I've tried the

I am sure it does get that %. I just did a similar implementation like rebel's
    evaluate internal nodes
    if(score - our maximum hanging piece > beta)
       don't do null move
  This gives me usually >93% effectiveness! Thanks Ed.

>recommendations listed there but they didn't help much.
>
>Michael



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.