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Subject: Re: Transpositions are driving me crazy !

Author: Gian-Carlo Pascutto

Date: 08:54:35 03/29/02

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On March 29, 2002 at 11:15:18, Oren Avraham wrote:

>1) Do I use the values stored in the TT when i'm scanning with Iterative Deeping
>? (example: values from depth 4 are not accurate (and even misleading) in depth
>5 (and so on...)

Correct. What info you _can_ get out of the TT is the best move,
and use this in move ordering.

>2) How do i use the Upper/Lower Bounds and when.
>    the lines :  if lowerbound >= beta return lowerbound
>                 else break;
>
>   confuse me - why this condition is checked - the values should be correct in
>all the cases because a rescan will generate the same cutoffs ...

A lowerbound means: the TT indicates this position is at least this good
Beta means: if the position is this good you don't need to look any further

Combine the two, and you see that you can take a cutoff immediately.

I don't understand what you mean with ' the values should be correct in all
cases ?'

--
GCP



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