Author: Roberto Waldteufel
Date: 11:33:17 08/03/98
Go up one level in this thread
Hi Bob, Maybe I am misunderstanding what happened, but something sounds a little strange here. When the search first finds that the pawn can't be held and fails low at the root, it gives you an upper bound on the position that is less than the value you previously used for beta by about the value of a pawn, so surely at this point you re-adjust the search window at the root to take account of this, so that when you re-search to depths 1,2 etc you do so with lower expectancy. The positions you reach in the researches should mostly have bounds stored from the search that failed low to start with, so I don't see why the search should keep failing repeatedly unless you hit hash records from lower depths (before the initial fail-low) and allow the lower depth re-searches to fail high and override your upper bound from the orriginal fail high, but could you not easily prevent this from happening by disabling the researching process until you had reached your previous depth again? I would be surprised if Schaeffer is recommending something as useless as you make it sound. Best wishes, Roberto
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.