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Richard Vida

Joined: 16 Apr 2009
Posts: 467
Location: Slovakia, EU

Post subject: Re: stand pat or side to move bonus    Posted: Sun Mar 25, 2012 3:21 pm

lkaufman wrote:
rvida wrote:
lkaufman wrote:
rvida wrote:
 lkaufman wrote: So the question can be re-phrased, do you believe that the decision to stand pat in quies should be based on a different score than is used for various pruning decisions in the main search? Using methods (B) or (C) would imply this. If so, why?

You use the same score everywhere with both methods (A) and (B), you just have to adjust margins. If you include tempo bonus in evaluate(), all your margins (used for 'various' pruning decisions in the main search) are offset by that value.

I notice that Critter evaluates symmetrical positions near the opening as +.05. If you don't give a bonus in evaluate but only use the bonus for stand pat decisions, what accounts for the displayed .05 score? Is it purely something added for display purposes only?

Please give a specific example. Without knowing the position I can only say that most probably it is exactly because of the reason you stated. (Tempo bonus is added to the stand pat score).

I tried symmetrical openings like c4 c5 or d4 d5 Nf3 Nf6 or f4 f5 Nf3 Nf6 on 2 and 3 ply searches. Since you include positional moves in quiesce it's not so simple to get a symmetric pv, but whenever the displayed pv resulted in a symmetrical position, the score was always .05. Now unless you've changed things since you sent me code, your stand pat offset in the qsearch was 26 points out of 256, which is 0.10. It is of course quite logical that the displayed score should be half of the value of a full tempo, but what causes this to happen? What code results in all symmetric positions on a full board showing as +.05?

Mystery solved. You are probably looking at the wrong piece of code. Tempo is defined in eval.h as 13 points out of 256, which is 0.05

The constant 26 you are reffering to is in qevasions(), and is used as a margin for pruning quiet evasions. Not related to tempo nor standpat.
 Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First
Subject Author Date/Time
Larry Kaufman Thu Mar 22, 2012 9:15 pm
Sam Hamilton Thu Mar 22, 2012 10:49 pm
Daniel Shawul Thu Mar 22, 2012 11:27 pm
Larry Kaufman Fri Mar 23, 2012 12:40 am
Daniel Shawul Fri Mar 23, 2012 1:27 am
Larry Kaufman Fri Mar 23, 2012 2:06 am
Daniel Shawul Fri Mar 23, 2012 3:07 am
Larry Kaufman Fri Mar 23, 2012 3:26 am
Richard Vida Fri Mar 23, 2012 2:07 pm
Larry Kaufman Fri Mar 23, 2012 2:42 pm
Richard Vida Sat Mar 24, 2012 9:59 am
Larry Kaufman Sat Mar 24, 2012 2:44 pm
Richard Vida Sun Mar 25, 2012 1:51 pm
Larry Kaufman Sun Mar 25, 2012 2:44 pm
Re: stand pat or side to move bonus Richard Vida Sun Mar 25, 2012 3:21 pm
Larry Kaufman Sun Mar 25, 2012 3:40 pm
Marek Kwiatkowski Fri Mar 23, 2012 2:46 pm
Richard Vida Fri Mar 23, 2012 2:01 pm
Robert Hyatt Fri Mar 23, 2012 2:38 pm
Larry Kaufman Fri Mar 23, 2012 2:47 pm
Uri Blass Fri Mar 23, 2012 3:39 pm
Larry Kaufman Fri Mar 23, 2012 3:45 pm
Robert Hyatt Sat Mar 24, 2012 3:03 am
Larry Kaufman Sat Mar 24, 2012 3:14 am
Robert Hyatt Sat Mar 24, 2012 4:41 am
Marco Costalba Sat Mar 24, 2012 8:12 am
Robert Hyatt Mon Mar 26, 2012 5:32 am
Sam Hamilton Mon Mar 26, 2012 2:12 pm
Robert Hyatt Sat Mar 24, 2012 3:00 am
Larry Kaufman Sun Mar 25, 2012 7:53 pm
Sune Fischer Sat Mar 24, 2012 10:38 am
Vincent Diepeveen Sun Mar 25, 2012 9:08 am
Uri Blass Sun Mar 25, 2012 11:24 am
Vincent Diepeveen Sun Mar 25, 2012 2:15 pm
Ed Schroder Sun Mar 25, 2012 1:02 pm
Larry Kaufman Sun Mar 25, 2012 7:43 pm
Ed Schroder Sun Mar 25, 2012 8:37 pm
Larry Kaufman Sun Mar 25, 2012 8:51 pm
Richard Vida Sun Mar 25, 2012 9:33 pm
Larry Kaufman Sun Mar 25, 2012 9:48 pm
Don Dailey Sun Mar 25, 2012 10:15 pm
Vincent Diepeveen Mon Mar 26, 2012 10:48 pm
Richard Vida Tue Mar 27, 2012 9:59 am
Vincent Diepeveen Tue Mar 27, 2012 11:38 am
Ed Schroder Sun Mar 25, 2012 10:39 pm
Larry Kaufman Sun Mar 25, 2012 3:49 pm
Vincent Diepeveen Sun Mar 25, 2012 4:20 pm
Larry Kaufman Sun Mar 25, 2012 4:47 pm

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