Author: Tony Werten
Date: 19:25:02 11/23/02
Go up one level in this thread
On November 23, 2002 at 22:14:27, Omid David Tabibi wrote: >On November 23, 2002 at 21:50:01, Tony Werten wrote: > >>On November 23, 2002 at 21:24:08, Omid David Tabibi wrote: >> >>>On November 23, 2002 at 21:09:36, Tony Werten wrote: >>> >>>>On November 23, 2002 at 20:52:01, Omid David Tabibi wrote: >>>> >>>>>On November 23, 2002 at 20:00:15, Tony Werten wrote: >>>>> >>>>>>On November 23, 2002 at 11:11:16, Christophe Theron wrote: >>>>>> >>>>>>>On November 23, 2002 at 09:22:37, jefkaan wrote: >>>>>>> >>>>>>>>oops, wasn't finished yet.. >>>>>>>> >>>>>>>>>are done by using the results of the positional eval >>>>>>>>>to prune the q-search, >>>>>>>>and there using only material eval >>>>>>>> (haven't tried it out yet, and wouldn't >>>>>>>>know how to do it, but it's only an idea, >>>>>>>>you know.. to explore options of >>>>>>>>more effective branch factor reducements >>>>>>>>and efficient programming (besides >>>>>>>>lousy solutions as inline assembler >>>>>>>>and bitboards.. >>>>>>>>:) >>>>>>> >>>>>>> >>>>>>> >>>>>>>Yes Chess Tiger does much more pruning than known (published) techniques. >>>>>>> >>>>>>>I think other top programs do it also. >>>>>>> >>>>>>>I still fail to see why the efficiency of an algorithm depends on what your >>>>>>>QSearch does. >>>>>>> >>>>>>>If your pruning algorithm is good, it will increase the strength of the program >>>>>>>regardless on how good your QSearch is. >>>>>>> >>>>>>>If your QSearch is smart, then it will increase the strength even more. >>>>>>> >>>>>>>I don't like the idea that some algorithms that have almost nothing to do with >>>>>>>each other would have such an influence on each other. It is indeed possible and >>>>>>>it probably happens all the time, but it's hard to work with such hypothesis in >>>>>>>mind. >>>>>>> >>>>>>>I think it's better to first assume that the kind of QSearch you do will not >>>>>>>interfere with the quality of the pruning algorithm used before the QSearch. >>>>>>> >>>>>>>If your QSearch sucks, it's not because you are doing a lot of pruning in the >>>>>>>"full width" part of the search. It's because it sucks. >>>>>> >>>>>>The paper does prove that the more your (q)search sucks, the better your pruning >>>>>>algoritm seems. But that's not really news. >>>>>> >>>>> >>>>>Does it prove that?! No, it's just my impression based on the data gathered so >>>>>far. Maybe a reduction of 2 (instead of 1) in case of fail-high report, will >>>>>work better in programs with heavy extensions and quiescence. >>>> >>>>A reduction of 20% seems to be working best in XiniX ( heavy qsearch). >>> >>>What do you mean by 20%? (you used a reduction of 1 or 2 in case of fail-high >>>report?) >> >>In case of a fail high I reduce the depth with 20%. ( doesn't work in your silly >>program :) >> > >Anyway, no matter what the reduction is, you are using verified null-move >pruning, which is good :-) In my paper I just gave a new null-move pruning >framework; feel free to play with the values that best fit your program. It's a no brainer to implement. If it's not bad then it's worth investigating. > >Even better values do exist. I've been working on them for some time and will >publish them in near future. If I might give an advice. For first reviews, send them it to some active chessprogrammers, and not to academic has beens. It will save you a lot of typework. ( you have been quite active on this forum lately ) BTW last time we mailed I concluded your last name was David, were does the Tabibi come from ? Tony > > >>In XiniX I have partial extensions (PLY is 32). >>The addition to your idea is to give big reductions when there is still a lot of >>searchdepth remaining. So fe when there is 12 ply left I give more reduction >>than when there's 6 ply left (with a minimum of 1 ply ) That's 6*0,2 is 1,2 ply >>more. For XiniX that seems to make the difference between a good and a bad new >>idea. >> >>Tony >> >>> >>> >>>>I'm >>>>interessed in your idea. It's commented out in my program now, but not deleted. >>>>I still have to play with it some more. >>>> >>>>Despite of the negative comments you had, I don't think it's a bad idea. I'm >>>>just not convinced yet it's a good one. >>>> >>> >>>It took me several months of experiments to get convinced. After a little more >>>tuning and playing with different reduction values (1 or 2), I believe you will >>>be convinced too ;-) >>> >>> >>>>Tony >>>> >>>> >>>> >>>>> >>>>> >>>>>>Tony >>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> Christophe
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.