Author: Uri Blass
Date: 05:14:02 12/28/01
Go up one level in this thread
On December 28, 2001 at 07:38:24, Rafael Andrist wrote: <snipped> >2) a) re-do the qsearches without limit (if you don't hash qsearch, this is >expensive) I do not hash nothing for now. I think that there are more important things to improve in my program than implementing hash tables. I believe that programs earn more from null move pruning than from hash tables and my program also is not a null mover. I also remember that not hasing qsearch is used by part of the top programs. old Fritz versions used to hash qsearch nodes and it is the reason that they needed hash tables more than the new Fritz. <snipped> >>3)using special evaluation(SEE) when >>there are captures but you cannot search deeper >>because of your limit(SEE is used in crafty only >>for pruning captures in the qsearch >>or for order of moves and not for evaluating >>and this is the reason that I did not use the word SEE >>because I did not do a connection between SEE and evaluation >>function). > >This sounds like a good idea. Since static eval may have some problems with >pinned pieces, a detection of "simple" positions which can be evaluated >statically may be useful. In the other cases you could extend the qsearch limit >a bit. if you extend the qsearch too much you may get often irrelevant positions that you analyze. The problem is that one of the players could win the game by a move that is not included in the qsearch. The probability for it increases when the number of plies increase and it seems clear to me that if you search deep enough the score that you have is often not relevant because you can be almost sure that the score in the qsearch for one of the previous nodes is wrong so you earn less information from searching more nodes and at some point common sense says that you need to stop because you pay more than you get. Uri
This page took 0.02 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.