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Subject: Re: stuffing moves in hashtable, fail low

Author: José Carlos

Date: 12:10:57 12/01/99

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>Maybe here is the problem:
>I once searched the position with a fixed alpha-beta window and got a fail low
>and stored the value.
>Now i come back to this position with an other alpha-beta window. The stored
>value is lower than alpha, so I use it. (the problem!)
>Can this be incorrect? Can with this new alpha-beta window come out a value in
>the search, which is not a fail low, cause some beta-cutoffs are handled another
>way deeper in the search?
>
>Werner

  Hi Werner!
  If I'm not sure if I understand what you call "the problem". This is what I
think: a fail-low implies that the returned value is an upper bound for the
"real value". So, if I reach this position with a different ABWindow, if the
value stored in the hash table is below the new Alfa, it is perfectly valid for
failing low again, since the real value _is_ surely below it.

  José C.



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