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Subject: Re: What means lazy/plain alpha bounding?

Author: Severi Salminen

Date: 13:22:12 02/07/01

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Hi!

Thanks for detailed explanation.

>1.  You might start the next iteration without a PV to guide the search.
>Internal iterative deepening helps.

Oh, a new term again: internal iterative deepening. I think this was the thing I
wondered in Crafty's search.c. Do you use IID in other places than when you are
in PV node and don't have a move to try? Has anyone ever tried to use IID in
_every_ node? If it helps in the root why wouldn't it help in other nodes as
well...

>I don't do this in Crafty for lots of reasons.  Null-move + hashing can cause
>false fail-highs on a null-window search, and if you automatically assume that
>move is better, you will make horrible mistakes every now and then.  In crafty,
>if the null-window search fails high and the re-search immediately fails low,
>I pretend the fail-high never happened.

I also think I'll skip the lazy alpha bounding and stick with the plain alpha
bounding I seem to be using. I want to keep things as simple as possible.

Severi



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