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Subject: Re: Disequilibrium schemes

Author: José Carlos

Date: 03:39:55 10/23/03

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On October 23, 2003 at 06:19:14, Uri Blass wrote:

>On October 23, 2003 at 05:34:29, Tony Werten wrote:
>
>>On October 23, 2003 at 04:43:31, Sergei S. Markoff wrote:
>>
>>>Hello!
>>>
>>>>In case you forgot, the evaluation can just return 1 score
>>>
>>>Oh when I was such simply guy
>>>Than I was clean and brave :)
>>>
>>>>score it can't return 2 scores for either positional or tactical matters.
>>>
>>>The matter is not about the returning more than one score in search. The matter
>>>is to use eval disequilibrium in current node to make some descisions. It can
>>>affect search or evaluation itself.
>>>
>>>But, anyway, it's not impossible to use two scores. One example Centaur program
>>>which uses two evals - pessimistic and optimistic. It's allows to produce good
>>>cut-offs where optimistic eval < alpha or pessimistic > beta. I don't know
>>>detatil but it seems to be interesting concept.
>>
>>Not really. It has been used for years, only most people use the term lazy eval.
>>
>>Pessimistic score: simple eval-maximum positional score
>>Optimistic score : simple eval+maximum positional score
>
>This is not what I think about when I read pessimistic and optimistic.
>
>By this definition the difference between passimistic and optimistic is
>constant.
>
>I think about calculating 2 bounds when in quiet positions the difference
>between the bounds is small when in not quiet position the difference is big
>
>Uri

  Kind of my "uncertainity degree", which tells me how likely is the static eval
to be worthless :)

  José C.



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