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Subject: Re: Speaking of the Thesis by Marcel van Kervinck (hopefully no storms)...

Author: Uri Blass

Date: 17:34:14 09/06/02

Go up one level in this thread


On September 06, 2002 at 19:16:56, Tony Werten wrote:

>On September 06, 2002 at 17:45:15, Uri Blass wrote:
>
>>On September 06, 2002 at 15:46:53, Tony Werten wrote:
>>
>>>On September 06, 2002 at 14:45:11, Dann Corbit wrote:
>>>
>>>>Did anyone notice his cutoff idea in the evaluation function?
>>>>
>>>>It seems to me to be a very good idea, and I don't know if others have tried it
>>>>out.
>>>>
>>>>Basically, it consists of three modes with two early exits...
>>>>
>>>>1. If the material + structure score alone is dominant enough, it exits right
>>>>away.
>>>>2. Otherwise, it processes the piece list.  If that score is dominant, it exits.
>>>>3. Otherwise, it does a full board control scan for all 64 squares.
>>>>
>>>>It is described starting on page 62 under the section "3.3.2 Multi Staged
>>>>Design"
>>>>He gets roughly 71% evals returning in stage #1, 13% in stage #2 and 7% in stage
>>>>#3.
>>>>
>>>>It seems like it might be a big win to do it that way.
>>>
>>>It's called lazy eval and is not a good idea. The times it is wrong happen to be
>>>the important ones.
>>>
>>>Tony
>>
>>I use incremental evaluation.
>>The only cases when I can be wrong in being lazy is in my qsearch because I do
>>not make every stupid capture in my qsearch.
>
>Why not ? If you make the supid capture and call quiescence, it will jump out of
>it because eval>beta.
>
>Anyway, since you have told here everal times that Movei doesn't have a complete
>eval yet, your experiences don't really impress ( not meant unfriendly !) The
>less knowledge your eval has, the better lazy eval works.
>
>Tony

The point is that for movei making moves is expensive so not to do it save time.
I think that if I make every stupid capture then it means that the program may
be clearly slower.

The problem is that making moves including updating the attack arrays.


I guess that for xinix making moves is relatively cheap and most of the time is
used in the evaluation function.

Am I right?

Uri



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