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Subject: Re: SEE and FH-%

Author: Dan Honeycutt

Date: 12:01:21 03/30/04

Go up one level in this thread


On March 30, 2004 at 14:14:24, Robert Hyatt wrote:

>On March 30, 2004 at 13:55:47, Andreas Guettinger wrote:
>
>>On March 30, 2004 at 13:16:00, Robert Hyatt wrote:
>>
>>>On March 30, 2004 at 12:29:42, Renze Steenhuisen wrote:
>>>
>>>>
>>>>Hi all,
>>>>
>>>>today I wanted to implement SEE, and use it in the Qsearch. My SEE isn't using
>>>>X-ray (discovered attacks) at the moment, but I already expected to see a boost
>>>>in FH-%. Unfortunately I didn't see it yet...
>>>>
>>>>Using it in the main-search did give an advantage of some 5%
>>>>
>>>>1> Is SEE not that important in Qsearch?
>>>>
>>>>2> With MVV/LVA I had about 15-20% Quiscence nodes, with SEE I have 25-30%
>>>>   Qnodes!?
>>>>
>>>>Could some one give an overview of which move-ordering technique is responsible
>>>>for how much FH-%?!
>>>>
>>>>Thanks!
>>>>
>>>>Renze
>>>
>>>If you use SEE everywhere for move ordering, it will reduce the total tree size
>>>by about 10% over MVV/LVA.  But if you use SEE to eliminate hopeless captures in
>>>the tree search, you will reduce the tree size by more than 50%, which is very
>>>significant.  MVV/LVA can't be used to do this since it is a poor estimator for
>>>expected gain or loss...
>>
>>
>>Do you mean by eliminate hopless captures in the tree search:
>>
>>- give them the smallest priority in move ordering?
>>
>>or
>>
>>-prune them in the search tree?
>
>Prune in q-search.  I am having a hard time typing until my hand recovers.  I
>didn't write that very clearly.  I eliminate losing captures _only_ in
>q-search...
>
>
>
>>
>>regards
>>Andy

Related question which takes little typing - is it worth the cost to include
pins in the SEE?

Dan H.




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