Author: José Carlos
Date: 16:20:57 12/20/04
Go up one level in this thread
On December 20, 2004 at 19:16:12, Uri Blass wrote: >On December 20, 2004 at 18:57:54, José Carlos wrote: > >>On December 20, 2004 at 18:43:19, Uri Blass wrote: >> >>>On December 20, 2004 at 18:31:56, Dann Corbit wrote: >>> >>>>On December 20, 2004 at 18:27:37, Uri Blass wrote: >>>> >>>>>On December 20, 2004 at 18:22:24, Dann Corbit wrote: >>>>> >>>>>>On December 20, 2004 at 16:32:24, Jouni Uski wrote: >>>>>> >>>>>>>Shredder 8 reaches quite stunning averaga search dept. E.g. with only 15 >>>>>>>second/move average with Pentium 2400 and 128MB hash it averages 15,2 ply! For >>>>>>>comparison Fritz Bilbao and Gandalf 6 reach both same 12,7 ply. No wonder >>>>>>>Shredder beats them 13 - 7 and 14 - 6. Of course 2,5 ply is a lot difference! >>>>>>>Is there any amateur or pro engine, which can equal Shredder in depth - Junior's >>>>>>>half plys can be forgotten. >>>>>> >>>>>>I can write an evaluation function that only counts the wood. It will beat >>>>>>Shredder's depth, but Shredder will easily kill it on a 1/10 as powerful machine >>>>>>all the time. >>>>> >>>>>Only writing evaluation that only count wood will not be enough to beat >>>>>shredder depth. >>>> >>>>A simple PVS with null move and wood counting only will get 19 plies in a few >>>>seconds. Is that what you mean by pruning? >>> >>> >>>In what position? >>>I never had only wood counting but I guess it is dependent on the position and >>>in tactical position when there are many threats to win material it may get >>>smaller depthes. >>> >>>Uri >> >> Only material eval gives much more cutoffs in alphabeta because most evals are >>equal, so basically everything that doesn't lose material (compared to the PV) >>gets immediately pruned. >> >> José C. > >I understand. >This is the reason that I said that in tactical positions when there are many >threats to win material it may get smaller depth. > >Uri IIRC, the author of SOS did an experiment some years ago (it must be in the archives): he tried the starting position with SOS only-material and reached depth 30 after several hours. Of course the starting position is not very tactical :) but I guess along 30 plies there were some tactics in between... But don't trust my memory. I have the worst memory on earth. José C.
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.