Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Should an engine using SEE beat another not using it?

Author: Severi Salminen

Date: 14:47:28 01/28/01

Go up one level in this thread


>If the only difference is SEE vs MVV/LVA, I generally find the two work
>about equally well.  SEE will search a 10% smaller tree, but will use 10%
>more time per node.  Breaks even.  MVV/LVA is the opposite.
>
>But if you use SEE to eliminate bad captures in the q-search, then you
>can make the SEE program 2x faster than the non-SEE program.  That should
>begin to make a difference.

Dang. My version without SEE is 2x as fast as the one with SEE (in NPS). It sure
shrinks the trees but as said the speed drops a lot. In Qsearch I don't try
moves if material+see_score(move)+PAWN_VALUE<=alpha or if see_score<0. For some
reason the SEE is very slow to calculate. I do it in same fashion than in Crafty
and it shouldn't be very slow. I assign SEE value to every capture at the same
time they are generated and if the value of piece being captured<= value of
capturing piece. Else I assign the difference. Then I sort them and start
searching. There must be something I am missing, or maybe not. It seemed that at
longer time controls the version with SEE played tactically better. How much
does Crafty get speedup in NPS if you remove SEE? And what do you mean by 2x
faster. Searches to same depth 2x faster or what? Should the SEEless version get
beated by the one with it?

Severi



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.