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Subject: Re: Question about static exchange evaluation

Author: Larry Coon

Date: 14:42:15 11/14/98

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On November 13, 1998 at 17:17:32, Robert Hyatt wrote:

>The "loss" occurs because this is used for move ordering.  If you
>don't "play out" all the captures, you might assume you can win a
>rook, or you might assume you win the exchange, and quit early.  If
>you use this score for ordering captures, you might look at the wrong
>one first...

Unless I'm missing something, cutting off early never
leads you to confuse a won exchange with a lost one,
only the exact material amount that is won or lost.

>>Side note, and I asked this in another branch of this
>>thread -- are there criteria that determine when you do
>>and don't do a SEE, or do you always do one when you're
>>in evaluate() and there are pieces under attack?

>I don't do *any* of this in evaluate.  I use SEE to order captures, and in
>the q-search, to cull captures that seem hopeless...

Ah, see what I mean about reinventing the Edsel?  :-)

I was actually looking for ways of mitigating the horizon
effect, and assumed that SEE was a cheap way of pseudo-
extending the search.  I frankly never considered it for
move ordering, but now that you brought it up....  :-)

Has SEE been tried for use in evaluate() and found lacking?
If so, was the overhead too high, or the benefit too low?

(My next question, had my premise about SEE and the horizon
effect been correct, would have been about seeing through
the use of interposition to create the horizon effect.)

Larry Coon

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