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Subject: Re: Latest Carfty Se happenings

Author: Robert Hyatt

Date: 21:16:56 10/06/04

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On October 06, 2004 at 19:09:21, Uri Blass wrote:

>On October 06, 2004 at 17:22:47, Robert Hyatt wrote:
>
>>On October 06, 2004 at 15:41:18, Peter Berger wrote:
>>
>>>On October 06, 2004 at 15:25:16, Peter Skinner wrote:
>>>
>>>>I think the main reason for that is flawed testing, testing on 1 pc with ponder
>>>>on....
>>>>
>>>>Most people do not use the correct books, proper rc file settings, and well just
>>>>about anything else that can go wrong.
>>>
>>>Quite irrelevant, as there is little reason to assume that they changed their
>>>testing habits recently in a way that would hurt 19.17's performance. Also the
>>>book discussion has gone a little out of hand recently, if you ask me.
>>>
>>>> *   19.16   fix to "Trojan code" to eliminate the time limit exclusion since  *
>>>> *           many users still have old and slow hardware, and the time limit   *
>>>> *           was not set correctly when PreEvaluate() was called anyway.  the  *
>>>> *           code to display fail-high/fail-low information was cleaned up so  *
>>>> *           that the +1 or +3 now makes sense from the black side where the   *
>>>> *           score is really going down (good for black) rather than showing   *
>>>> *           a +3 fail high (when Crafty is black) and the score is really     *
>>>> *           going to drop (get better for black).  Now the fail-high-fail-low *
>>>> *           +/- sign is also relative to +=good for white like the scores     *
>>>> *           have been for years.  adjustments to pawn evaluation terms to     *
>>>> *           improve the scoring balance.  "new" now terminates parallel       *
>>>> *           threads (they will be re-started when needed) so that we don't    *
>>>> *           burn CPU time when not actually playing a game.                   *
>>>> *                                                                             *
>>>> *   19.17   changes to pawn evaluation to limit positional scores that could  *
>>>> *           get a bit out of sane boundaries in some positions.               *
>>>> *                                                                             *
>>>> *******************************************************************************
>>>>
>>>>Really there is the removal of useless code, and fixs to scoring. That is about
>>>>it. Nothing significant between the two.
>>>>
>>>
>>>Reads different to me. At least the changes for 19.17 could well be relevant,
>>>judging only from the text above. Also sometimes there are changes with
>>>unexpected effects.
>>
>>That change likely had no affect on most games.  It only changed things in
>>_very_ awkward positions such as where one side has 6-7 isolated pawns and the
>>like, which is not going to happen often...
>
>I read also in 19.16
>adjustments to pawn evaluation terms improve the scoring balance.
>
>Is this another change that has no affect on most games?
>
>Uri


Yes.  It was a "zero sum change".  IE do you add 16 for this and start at zero,
or do you add 16 for this and start at -8.  All it really does is change the
"origin" for scores, so that base scores don't start at +.5 or whatever, but
closer to 0.0...




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