Author: Georg v. Zimmermann
Date: 02:56:25 12/09/00
Go up one level in this thread
>> >>But this wont happen if your margin is large enough. As large as your largest >>position scores. As explained by Ernst. Very simple. And accurate. > > >Yes... but if the margin is "big enough" then you don't have futility pruning, >either. That is the problem. And if you eliminate _one_ node from the tree >search, you stand the chance of perturbing the score that eventually backs up >to the root of the tree, due to the hash table. > >The problem with "big enough" is that for some programs, "big enough" might be >a pawn or two. For other programs it might be way more than a queen. Such a >window effectively disables futility pruning. For those that want to produce >very large positional scores. What I am doing is to set value = fmax = eval(); instead of materialeval(). That way your margin can be the maximum eval change in 1ply only. This obviously only works if your eval() is very fast. If not, you can try to write another fasteval() function which only uses those eval parts than can get very big, king safety for example. I got good results with that. Regards, Georg v. Zimmermann
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.