Author: Dann Corbit
Date: 20:49:15 03/06/06
Go up one level in this thread
On March 06, 2006 at 23:45:06, Nathan Thom wrote: >On March 06, 2006 at 23:40:58, Stuart Cracraft wrote: > >>On March 06, 2006 at 23:36:22, Dann Corbit wrote: >> >>>On March 06, 2006 at 22:14:27, Nathan Thom wrote: >>> >>>>>>3. Search inefficiency (branching factor of a good program is definitely under >>>>>>4) >>>>> >>>>> * My branching factor is about 2-3 for these kinds of positions. >>>> >>>>How are branching factors calculated? I get wildly different values at each ply >>>>as each side usually has different numbers of moves available to them... and at >>>>the root node, its always the full number of moves isnt it? >>>> >>>>e.g, for 8/6k1/6Pp/3r1P2/6K1/n3BP2/1p6/4R3 w - - 3 51 >>>>I get branching factors at each ply of 26 2 20 4 16 3 13 3 10 >>> >>>The simplest and most accurate way to determine your branching factor is to >>>divide the time to complete iteration N+1 by the time to complete iteration N >>>(don't bother computing it if you had an interrupt halt calculations -- >>>calculate it only if it finished naturally). >> >>That's what I do, then I average them all together for the current >>iterative deepening 1-N set for the given search. >> >>After that I average all those averages together across a test suite >>to get the final branching factor. >> >>The former are br= in my listing and the latter are bf= which is an ongoing >>average of the averages. >> >>Stuart > >ahhh, that would be why mines so different. i actually keep track of the actual >number of moves followed at each ply which to me is what branching factor means. Look at your counts: Hi,low,hi,low... I think it is hash table that does that with your program, but I guess if you calculate the time you will not see the same crazy oscillations. You should not see branching factors near 30 unless you are using mini-max. Are you not using alpha-beta?
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.