Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: real job of the qSearch? find quiet vs stop horizon effect

Author: Russell Reagan

Date: 13:11:55 08/28/03

Go up one level in this thread


On August 28, 2003 at 10:18:56, scott farrell wrote:

>When you read most literature it says "to find quiet positions" so the eval
>function is more accurate, and the quiescent in the name suggests the same. But
>I think this is wrong, and most people use it for the later.

The goal of quiescence search is to find quiet positions to evaluate, and I
think that the reason that the vast majority of people use good captures, pawn
promotions, and maybe checks is because it is very easy to determine that those
are almost always forcing moves.


>I have a few positions where a black pawn cant be stopped because of wrong
>colour bishop

>So it is the qSearch's job to find quiet or to stop some classes of horizon
>problems?

I think that there are a ton of extra classes of moves that you could add to the
quiescence search, but the closer you get to "perfect" qsearch, the closer you
get to full width search. For instance, maybe a move that seems very quiet
actually threatens a mate in 10. The only way to include that kind of move in
your qsearch is to do a deep search.

Maybe there are some alternative methods that would work well for detecting
something like that, such as proof number search. Even then, doing a proof
number search at each node in the qsearch would be rather expensive, and it
probably won't find any vital forcing moves anyway (in the majority of
positions), and there would still be many other subtle moves you wouldn't
detect.



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.