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Subject: Re: evaluation tuning tricks

Author: Fabien Letouzey

Date: 08:15:30 03/17/04

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On March 17, 2004 at 11:10:00, Renze Steenhuisen wrote:

>On March 17, 2004 at 11:07:03, Fabien Letouzey wrote:
>
>>On March 17, 2004 at 11:04:25, Renze Steenhuisen wrote:
>>
>>>On March 17, 2004 at 10:25:24, Tord Romstad wrote:
>>>
>>>>On March 17, 2004 at 09:55:59, Fabien Letouzey wrote:
>>>>
>>>>>No offense Tord, but I don't understand  why programmers think the move ordering
>>>>>is "perfect" if a fail-high move is found first 100% of the time.
>>>>
>>>>Because the percentage of first-move fail-highs is easily measured?  Of course
>>>>I agree that the size of subtrees is important, but I don't see how you can
>>>>determine how often a fail-high move has a smaller sub-tree than all other
>>>>fail-high moves at the same node, except by searching the whole minimax tree.
>>>>
>>>>Tord
>>>
>>>What has move-ordering to do with the sizes of subtrees of siblings?
>>>
>>>Renze
>>
>>In PV nodes you want the move that leads to the best score.
>>
>>In null-window nodes you want the move that fails high after searching the
>>smallest subtree, not necessarily the one that leads to the best score.
>>
>>Fabien.
>
>
>Fabien,
>
>what are NULL-window nodes again? I know of PV-, ALL- and CUT-nodes...
>
>Renze

It's only my name for them, nodes that are searched with a null window (you
don't know yet if they will be CUT or ALL of course).

Move ordering never affects ALL nodes anyway (forgetting about transpositions).

Fabien.




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