Author: John Merlino
Date: 17:04:50 12/10/00
Go up one level in this thread
On December 10, 2000 at 18:55:18, William Penn wrote: >Here's an example of a position that flip-flops the sign attached to the score >when it goes above/below the critical 1.00 value: > >-- -- BR BR -- -- BK -- >BP BB -- -- -- -- BP BP >-- -- -- -- BP -- -- -- >-- -- -- -- WP BP -- -- >BQ -- -- -- -- -- -- -- >WP -- -- -- WQ WP WP -- >-- WP -- -- -- -- -- WP >WR -- -- -- WK WB -- WR > >(Black to move) > >When the score number is bigger than 1.00, the minus sign is attached. When the >score number is 0.99 or smaller, the minus sign is dropped (probably incorrectly >so). This evaluation is with the default Chessmaster personality and engine. >The same thing happens with custom defined personalities. > >Time Depth Score Positions Moves >0:00 5 -1.21 26737 Qc2 >0:02 6 -1.14 90450 Qc2 >0:07 7 0.90 269558 Qc2 >0:25 8 -1.08 871667 Qc2 >1:10 9 0.99 2628902 Qc2 >5:31 10 0.99 11104747 Qc2 >23:30 11 0.80 48168538 Qc2 > >WP > > > > >On December 10, 2000 at 17:55:12, William Penn wrote: > >>Please take a close look. I believe that James T. Walker has put his finger on >>the evaluation problem as expressed in scores: There is apparently a bug when >>scores are in the range of +1 to -1 which fails to put a minus sign on negative >>scores. The minus sign is only affixed to the score when it is less than -1. >>WP >> >> >>On December 10, 2000 at 17:11:19, James T. Walker wrote: >> >>>On December 10, 2000 at 16:58:07, William Penn wrote: >>> >>>>To Jeremiah & James... >>>> >>>>Thanks to Jeremiah Penery and James T. Walker for your replies and suggestions. >>>> >>>>For some unknown reason, I am unable to post a reply in the original thread >>>>below. I just get a message saying the thread doesn't exist, hasn't been posted >>>>yet, may have been deleted...etc. I may have a corrupted cookie, or something. >>>> >>>>There is a dearth of documentation about CM8000, and nothing in the instructions >>>>about such things. We are apparently dependent on John Merlino to come along and >>>>fill in the gaps, insofar as he knows the solutions/answers. I've heard from >>>>him before on this subject, and am not sure that he knows the answer. It may >>>>require the chess engine's author to take a look at it in a very patient way, if >>>>he is willing, but that could be a problematical proposition too!? >>>> >>>>Bottom line: I can't be confident in CM8000's scores generated when evaluating >>>>positions, and that's pretty fundamental. >>>>WP >>><snip> >>> >>>Hello William, >>>I have finally been able to understand the problem. You are right about >>>ChessMaster 8000 having a problem with the scores! All scores below 1.00 are >>>positive even when black is winning. As soon as the score goes over 1.00 for >>>black the scores show the minus sign. This is a definite error in the GUI. I >>>don't think the engine has a problem since it is playing so well (except for not >>>using it's time). I think it's just a bug in the scores below -1.00. I just >>>finished a game in which the score was around 0.97 and I'm sure black was ahead. >>> The scores then bounced from 0.97 to -1.01 back to 0.91. I'm sure the position >>>was not that wild. It's just that all scores below 1.00 are positive. I have >>>noticed this before but could not put my finger on the problem. I noticed that >>>ChessMaster seemed to always think white was winning untill something drove the >>>score past -1.00. Then it shows scores like -1.21 indicating black is winning. >>>This is definitely a problem for John to pass along. >>>Jim OK guys, that should be enough proof for the development team. Thanks for being so diligent about it. cm
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