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Subject: Re: Branching factor again ;-)

Author: Robert Hyatt

Date: 08:23:34 08/27/02

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On August 27, 2002 at 10:30:44, Steffen Basting wrote:

>On August 26, 2002 at 14:57:23, Robert Hyatt wrote:
>
>>On August 26, 2002 at 12:52:40, Steffen Basting wrote:
>>
>>>Hello!
>>>Some days ago, I posted about the bad branching factor in my chess program.
>>>Here's the output of the starting position as an example:
>Hi!
>>As far as your qnodes/eval counter, think about it for a minute.  Where do
>>you call evaluate() from?  The top of quiesce()?  :)  So for every call to
>>quiesce() there is an immediate call to evaluate().  The counters _should_
>>match.  :)
>Yes, your are right ;-)
>
>
>>>And is this strange branching factor due to a bad move ordering?
>>>Sorry if the positions i posted above don't show the problem. Perhaps you could
>>>make some suggestions which positions to use...
>>
>>What kind of ordering are you doing.  I noticed you said "no hashing" which
>>hurts.  What about null-move?  Without that your branching factor will be
>>pretty fat in most positions...
>
>Hi!
>I am using null move pruning. Move ordering is done by MVV/LVA and some sort of
>history heuristic.
>
>Steffen


what R value for null-move?  2?  If so, your branching factor should never go
above 4, except for an occasional bad position here and there.  But on average,
if it is above 4, there is a problem in move ordering or in the search...



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