Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Shredder don't know how to promote pawn?

Author: Dieter Buerssner

Date: 15:02:02 12/06/02

Go up one level in this thread


On December 06, 2002 at 05:23:02, Richard Pijl wrote:

>On December 05, 2002 at 11:40:34, Dieter Buerssner wrote:
>
>>On December 05, 2002 at 07:51:02, Gian-Carlo Pascutto wrote:
>>
>>>Some programs have a workaround that makes the ugliest
>>>appearances of this problem go away.
>>
>>Can you give an example, preferably from a real game, where known workarounds
>>would not make the problem go away?
>>
>>In the discussed case, probably even using the normal search time instead of
>>exiting search early after a mate score woulh have helped.
>>
>>>But that doesn't
>>>fix the problem - it still occurs everywhere else in the
>>>search tree.
>>
>>I don't understand this. Why should there be any problem in the search tree?
>>Until a "critical" situation is at the root, what should be the problem?
>>
>
>Tablebases might force a program in a position it doesn't know how to win, for
>example because the position is an exception to general rules. These positions
>are possibly avoided by the chessknowledge of the program, but lured into it
>because it sees a forced mate from the table bases. It might even sac material
>because of it.

Richard, can you please give an example (I asked the same question to GCP
without getting an answer).

I really thought about exactly this point, but nothing came into my mind, where
this should happen. Especially, all the positions I remember seeing posted here
in this context, were trivial wins.

It was less than 2 hours to implement something to avoid those cases of problems
with incomplete TBs. Several similar ideas have been posted here - all easy to
implement. I repeat myself - allmost allways not stopping the search early, when
seeing a mate score, would even be enough (but better fixes exist).

Cheers,
Dieter



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.