Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: interference between verified null move R=3 and transposition table

Author: Uri Blass

Date: 14:19:39 07/03/04

Go up one level in this thread


On July 03, 2004 at 14:45:24, Stuart Cracraft wrote:

>On July 03, 2004 at 07:12:24, David B Weller wrote:
>
>>Just a thought -
>>
>>When the reduced depth verification search fails high, what depth do you store
>>in hash? I think it should be original depth, right? Not the reduced depth.
>>
>>David
>
>I store the original depth in the hashtable after failed failhigh in
>null move verification.
>
>On the other hand, after extensions like pawn to 6th/7th, recapture,
>and the like, I store the increased depth in the hashtable.
>
>Hope this isn't too much against the grain. Still have a ton of bugs.
>
>Solve 152 out of 300 of the Win-at-Chess in 1 second though with
>everything enabled. If I disable null move verification I get 167
>out of 300 at 1 second.
>
>Wonder if null move has this tactical-reducing capability in other
>programs? -- So that I know if it is working through indirect evidence
>(besides direct evidence of depth, nodes, etc.)
>
>Anyone care to comment about that last question?

I think that if you solve 152 or even 167 out of 300 of the win in chess in 1
second then you have clearly bigger problem than null move pruning.

Tscp does not support FEN but I guess that even tscp that has no null and no
hash can get more than 167 out of 300 in one second.

Did you test that pawn to 6/7 extensions help you?
I do not extend pawn to the 6th.

I think that you did the mistake of implementing a lot of stuff without testing.
You should implement one thing at a time and test if it is productive.

I suggest that you delete null move and hash and extensions and test again and
only implement things that help you to score better in WAC.

Uri



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.