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Subject: Re: Root Position

Author: David Rasmussen

Date: 11:11:59 01/05/01

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On January 05, 2001 at 09:45:47, Robert Hyatt wrote:

>On January 05, 2001 at 08:05:26, David Rasmussen wrote:
>
>>What is the best way to sort moves at the root after each iteration?
>
>My approach is to (a) put the PV move from the previous iteration first.
>Sort the remainder of the moves based on the number of nodes in the subtree
>produced by each of the other moves...
>
>

OK. I do this too already.

>>
>>What is the best way adjust alpha and beta at the root after each iteration?
>
>center it around the value returned by the previous iteration.  Look at your
>output carefully to find your "swing" value.  This is the amount of score
>"swing" caused only by even/odd ply searching.  If yours happens to be zero,
>then just center the score on the last iteration value.  If you notice that
>your odd ply searches have a score about .15 higher than even ply searches for
>the same move, then factor that in.
>
>

OK.

>
>One problem if you do null-move, is to watch for cases where a root move fails
>high, then fails low on the re-search.  In that case I do _not_ make that move
>a PV move.

What do you do then?



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