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Subject: Re: Verified Null-Move Pruning, ICGA 25(3)

Author: Gian-Carlo Pascutto

Date: 03:45:30 11/22/02

Go up one level in this thread

On November 22, 2002 at 01:48:06, Robert Hyatt wrote:

>It isn't what he is claiming.  He claims that R=3 + verification is close to
>R=2 in nodes, and has fewer null-move failures.  His data seems to support >that.
>R=3 with a depth-1 verification ought to be fairly close to R=2, just based on
>pure math.  I'll leave it to you to figure out why...

I don't really agree.

I'm assuming you do the fairly intuitive math of 2+1=3 but things
are not so simple :)

R=3 verif. does a R=3 search, one depth reduction on fail high (which
makes it equivalent to R=1 without nullmoving at that ply, but it is
safe because you guaranteed your opponent has no serious threat), and
R=3 cutoffs everywhere below

R=2 does, well, R=2 cutoffs

It's not so obvious these are close in nodes. In fact, the paper itself
points of that the methods scale very differently.


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