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Subject: Re: Futility @ 1/Extended Futility @ 2/Limited Razoring @ 3 = % node reduce?

Author: Stuart Cracraft

Date: 16:51:17 10/19/04

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On October 19, 2004 at 16:34:32, GeoffW wrote:

>Hi Stuart
>Can you clarify what margin thresholds you used and was the distance to the leaf
>before or after you made a move ?
>     Geoff

Sure. Margins were 3 pawns for futility pruning at depth == 1 (before
the makemove), 5 pawns for extended futility pruning at depth == 2
(before the makemove), and 9 pawns for limited razoring at depth == 3
(before the makemove).

In the first two cases, if found to prune, the node simply isn't searched
and skipped to the next move. In the last case, if found true, then the
depth is decremented for that move only by one additional ply.

>>In your program if you have implemented futility/extended futility/and
>>limited razoring, what is your node reduction?
>>I don't get anything like the 60%.

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