Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: New(?) search idea.

Author: Bruce Moreland

Date: 16:10:22 01/22/98

Go up one level in this thread



On January 22, 1998 at 18:47:24, Robert Hyatt wrote:

>doesn't help...  notice that a fail high still takes N times as long as
>a normal fail low.  And *some* of those root moves may well fail high.
>
>1.  what initial window can be used?  Old score from last iteration?
>Can be off significantly with an extra ply added on.  If the initial
>window is too low, fail highs will be killingly costly.  If it is too
>low, everything might fail low and there's no useful info.  If the
>supposedly best move (last one searched) returns a value lower than
>expected, what do you do about all the others that failed low on that
>null window?
>
>2.  Suppose all moves fail low, including the supposed best one.
>research
>them all?
>
>IE I don't know how to make this efficient at all.  Alpha/beta depends
>on
>alpha and beta to limit the size of the tree.  This approach seems to
>need
>a hearty dose of witchcraft as well... :)

The author addressed much of this in his post.  I'm going to stop now.
I'm not an advocate for this technique.  I don't want to spend more time
explaining what he is attempting to do.

bruce



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.