Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Multi-ProbCut and Crafty : does it work ?

Author: Will Singleton

Date: 18:48:34 06/28/03

Go up one level in this thread


On June 28, 2003 at 15:34:04, Rémi Coulom wrote:

>On June 28, 2003 at 12:03:01, Will Singleton wrote:
>
>>On June 28, 2003 at 11:20:21, Frederic Louguet wrote:
>>
>>>I read an interesting paper from Albert Xin Jiang and Michael Buro about
>>>Multi-ProbCut and its implementation in Crafty. I have always been very
>>>skeptical about this pruning technique (for chess) but the paper is rather
>>>optimistic. However, the data presented does not seem very convincing from a
>>>statistical point of view (too few games, not enough opponents). So could Robert
>>>Hyatt tell us a little more about the effectiveness of this technique ? Does it
>>>_really_ work ?
>>
>>I don't know about crafty, but I can tell you my experience.  After messing with
>>the values of cutoffs(c), moves(m) and reduction(r), I use c=2, m=8, and r=3/4,
>>depending on depth.  Increasing m (number of moves to probe to try to get
>>cutoffs) slows you down and doesn't help accuracy very much, and any value
>>greater than 2 for c caused all kinds of unnecessary searching.
>>
>>I found it helps slightly in many cases, and has no effect or is slightly worse
>>in others.  I didn't quantify it, but I didn't get quite the results the authors
>>did.  But since it didn't seem to hurt, I left it in.
>>
>>Will
>
>I think you are confusing Multi-ProbCut with Yngvi Björnsson's Multi-Cut, which
>is very different.
>
>Rémi

Oops, that's what I get for doing it from memory.

Will



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.