Author: Robert Hyatt
Date: 10:09:04 01/20/04
Go up one level in this thread
On January 20, 2004 at 05:40:07, Sune Fischer wrote: >On January 19, 2004 at 21:41:57, Robert Hyatt wrote: > >>On January 19, 2004 at 20:09:08, Sune Fischer wrote: >> >>> >>>How can it be nonsense? >> >>Same way I described previously. You reach positions that were not searched >>with the same "criteria" as when the PV was searched... > >So? >My evaluation is not path dependent either. > >Are you saying a 5 ply PV on position X is good, but when we later in some other >parts of the tree search X with ply 5 or above the PV will be nonsense? Absolutely. I explained why. One sequence of 5 moves might have two checks. Another sequence to reach the same position might have no checks. Which resulting search will be more accurate? The one without the preceeding checks or the one following the checks? Think about "draft". > >I think you need to explain that to me very carefully. Done. :) > >>>Let's say you pick up a single pv move and then qsearch is called. >>>That would end the pv. >>> >>>The pv might lead to a bad position now, but it can't be considered nonsense >>>when you know what your qsearch can and can't resolve. >> >>If you don't hash the q-search, then obviously the PV will _never_ have any >>q-search captures in it. > >I wouldn't want it to, I want to know where the search ends and qsearch begins. >That is important if you want to interpret the PV correctly. You can do that if you want. I don't but it is trivial to add, since I do know where I copy the PV from the q-search and from the main search. > >>But when I was doing this, I did hash in the q-search. >>The same problem arises irregardless. Prior to the q-search, you can overwrite >>stuff. When you probe for "imaginary" positions beyond the end of the current >>hash-table-hit position, you can get anything. Good moves. Moves that don't >>go with the current PV. And with today's Crafty I would get no q-search moves >>at all, and they are often critical to see. > >I suspect your search is broken then. Suspect what you want of course. I suspect it is not broken myself... :) > >If you terminate a leaf position because you've run out of depth and you have in >hash that position stored with a decent depth, why not use that information to >get a more accurate score back down the tree? That's not what I said. I didn't mention "decent depth" at all... I just said "hash signature match". > >Something is fishy here. > >-S.
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.