Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: SEEing it is BLIND

Author: Tord Romstad

Date: 01:35:54 08/08/04

Go up one level in this thread


On August 08, 2004 at 01:47:12, Stuart Cracraft wrote:

>Now my new question is what features do you think would help in solving
>problems rapidly. Extensions?

Yes.  But be careful -- It is easy to introduce lots of extensions which makes
your engine very good at solving problems, but which greatly reduce the
playing strength in real games.  You should always play some test matches
before you decide whether you want to keep some new extension in your
program.

The most useful extensions for solving problems rapidly are:

1. Checks.

2. Single reply to checks.

3. Mate threats.  These can be detected statically, or by using the return
value of a null move search.  Extend if the null move search returns
-MATE_VALUE+Ply+2.

4. Attacking moves.  If you evaluate all internal nodes (as I do), compare
the value of the king safety component of the evaluation function before
and after a move is made.  If a move dramatically reduces the opponent's
king safety, you extend.

In order to avoid search explosions, you may want to use fractional
extensions.  I extend by a full ply only for checks.

Tord



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.