Author: Dave Gomboc
Date: 16:41:14 06/18/00
Go up one level in this thread
On June 18, 2000 at 15:50:43, Gian-Carlo Pascutto wrote: > >Hi all > >In the discussion of the 'Scalable Search Test' thread with >Ed Schroeder I mentioned that MTD(n,f) has the nice property >of making a fail-high pretty constant over time. I.e. the >search does not blow up as it does in a normal PVS searcher. > >Unfortunately it seems that this does not help when moving >up a ply...it even seems that the results of the MTD'ers >are quite terrible. > >The following though occured to me, if MTD allows you to take >small steps in the score plane, what about using fractional >ply increments to take smaller steps in the depth plane? > >Many of the best programs have now switched to fractional extensions. >Thus, fractional search depth must make sense. > >Iterative deepening is one of the most important improvements to AB >search. Thus, it makes sense too. > >Still, the programs use whole ply's in their iterative deepening >search. Why? It would make perfect sense to step in smaller increments >too. I feel this can even give improvements in tactical situations, >where the fractional extensions are triggered. > >I'm interested if someone has ever done or tested this before. Did it >work? What were the results? > >If you happen to have a program which uses fractional extensions, please >try it, and let us know how it works out. > >-- >GCP My impression is that Junior has been doing this for some time already. <shrug> Most of the awari programs I know of increase depth by 2 ply each time, though I'll grant that 2 is still an integer. :) Mine used 1.5, partially because I thought it would be funny. Of course, it's just a constant that can be easily changed to whatever. Dave
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.