Author: Peter Fendrich
Date: 01:57:07 08/15/03
Go up one level in this thread
On August 14, 2003 at 21:43:42, Ralf Elvsén wrote: >On August 14, 2003 at 15:27:06, Peter Fendrich wrote: > >>1FH = The ratio where the first generated move in the node is a Fail High. >> >>I experimented with removing the the hash table and became a bit surprised. >>Normally I have about 1FH = 95-96%. When I removed the hash table that figure >>raised to more like 1FH = 96-97% while the search depth, as expected, was >>decreased. >> >>Increased 1FH when removing the hash table. Is this normal? >> >>/Peter > >Hello > >I haven't done any chess programming in over a year now (cured :). As you say >yourself below, this could be a statistical fluctuation. But I'm with Uri here: >I remember implementing a special improvement in move ordering in my program. >It worked fine, the time to search to a certain depth decreased. However, the >measure you call 1FH got worse. I made the same interpretation as Uri, namely if >you produce crappy moves at one ply you can will get a lot of FHs at the next >and your statistics looks fine :) I actually had a more refined statistic then >you: >I had 1FH for each ply, it probably was opposite effects for the last ply and >the ply before that (can't remember for sure though) but there are more nodes >closer to the leafs and they dominate the statistics. Hope I made myself clear, >it's late at night... > >After that I didn't care much about this number anymore. > >Ralf You think you're cured? Why are you engaged in this discussion then ... :-) I bet you'll start again soon... Yes, Uri has a point. I agree on that but not necessary in this case. Hash moves are used as first moves only (in my program). Removing the hash moves should worsen the 1FH that is clearly defined as performance of the first move only. Your example, as you described it in another post, makes sence I think but you should get better values in other meassurements. 1FH is only one dimension. /Peter
This page took 0.01 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.