Author: Ed Schröder
Date: 03:20:15 01/07/03
Go up one level in this thread
On January 07, 2003 at 06:00:58, Uri Blass wrote: >On January 07, 2003 at 05:47:37, Ed Schröder wrote: > >>On January 07, 2003 at 05:05:31, Tony Werten wrote: >> >>>Hi Ed, >>> >>>your board tables seem to ignore xray attacks. >> >>xray attacks are done, it's only not mentioned as I thought it would be >>self-understood. >> >> >>>Is that because it doesn't matter too much, or because it's mainly used for move >>>ordering ( so it's only less effective but not wrong ) ? >> >>I use xray also for evaluation, for instance for mobilty, king safety, so xray >>must be done and in an accurate way, I will write a little about it in the >>mobility section. >> >>Ed >Hi Ed, > >I have 2 questions about the evaluation. > >1)Did you try to do incremental evaluation. I have tried it in the past, it was maddening, if you are in love with bugs, self-torture and headaches then doing incremental evaluation is the right path to go. >I think that incremental evaluation may be faster than doing the full evaluation >at every node until depth-1. It is faster of course, but don't hold your breath, you will have to restore things too when climbimg back in the tree (decremental evaluation), meaning things have to be done twice. On "incremental evaluation", you can of course put all things on stack and just copy things back but that is also costly. >The problem is that doing it without bugs is not easy espacially when you have a >big evaluation. Yes, that's why I never finished the job, the second reason: it wasn't that much faster. >2)Did you check that your full evaluation is really productive if you assume the >same number of nodes. >I remember that when I tested personalities of Rebel I found that knowledge=500 >changes it's mind more often so it needs more nodes to finish the same >iteration. Natuarally [Chess Knowledge = 500] beats [Chess Knowledge = 100] slightly based on fixed depth, but it loses with a big margin using a normal time control, remember the gain from Lazy Eval is over a factor of 3. Ed >knowledge=500 beat knowledge=100 with fixed depth but the interesting question >is if it also beat knowledge=100 with fixed number of nodes. > >Uri
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.