Author: Robert Hyatt
Date: 14:59:17 12/07/00
Go up one level in this thread
On December 07, 2000 at 16:09:32, Ernst A. Heinz wrote: >>If you use _any_ kind of pruning, you can perturb the root score. Thanks >>to the transposition table that grafts parts of the tree into odd places. >>There is no way to anticipate which branches are useless _here_ but the >>hash results might improve the results over _there_. And as a result, you >>can get different root move scores no matter how "sound" the pruning. > >But the effects you describe, Bob, are rather due to the >hash-table usage than to the pruning. They might also >occur if you just change your move ordering. Correct. However, the question he asked was could futility pruning affect the score at the root. The answer is yes, because of the transposition table problem... > >Anyway, in the case of futility pruning at frontier nodes >with a remaining depth of 1 ply they hardly matter (if at >all) because it simply lifts inevitable "stand-pat" beta >cutoffs at horizon nodes up one level in the search. > >=Ernst=
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.