Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Positions of known value?

Author: Pete R.

Date: 15:58:45 07/25/00

Go up one level in this thread


On July 25, 2000 at 14:12:46, Tom Kerrigan wrote:

>It would be nice to make a change to your evaluation function and get immediate,
>accurate feedback.
>
>So my idea is to get a huge collection of positions of known value (i.e., "white
>has a stronger position") and then see how well the known values correlate to
>the evaluation function's scores.
>
>Does anybody have any ideas for getting a high-quality collection of such
>positions? Or any comments on this approach in general?
>
>-Tom

I've thought about something similar, i.e. what if God handed you the perfect
eval for a number of positions, that would be wonderful.  Obviously if you could
have an eval function that produced the same score that GMs would give a
position each and every time, your program would be unbeatable. But it would be
a fairly intensive project to get reasonably accurate evals on positions.  How
many positions would you need?  If it's a reasonably small number you might take
them from something with computer-checked GM analysis, such as Nunn's Chess
Openings.  You could then cross-check those positions with a number of top
programs run to high depths to make sure no hidden tactics were missed.

However, couldn't you simply use existing test suites for the same purpose with
just a little tweaking?  For example suppose I am reasonably certain that a
given test suite position has the correct best move listed.  It follows then
that if you generate all legal moves from that test position, the condition you
want is that the position resulting from the best move has the highest eval.  In
other words your program will take the test position, generate one position for
each legal move from there and run the eval on each resulting position, and see
if in fact your eval weights the position resulting from the best move higher
than the rest.



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.