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Subject: Thanks that's helpful! (NT)

Author: Steve Maughan

Date: 05:56:36 12/15/00

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On December 14, 2000 at 06:50:45, Steve Maughan wrote:

>My program doesn't use fail soft atr the moment but I have been reading about it
>on the web.  I hadn't realised that with fail soft the score, if less than
>alpha, is an upper bound and if greater than beta is a lower bound.  I can see
>that this would be useful - but how useful is it in practice?
>
>A couple of things I can think of doing if this is the case:
>
>1) Back up the hash score with the returned value as the bound and NOT alpha or
>beta.  This would give more hash cutoffs but is it accurate when one has null
>move & futility pruning etc?
>
>2) Use the score as a better bound for a fail high - obvious but I can't see
>anyone doing it.  As an example Shredder 5 seems to fail high at +0.25 above
>current score then +0.50 above current score.  Surely if this fail soft property
>is robust there must be a better way.
>
>Are all of these insights correct?
>
>Regards,
>
>Steve Maughan



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