# Computer Chess Club Archives

## Messages

### Subject: Re: likelihood instead of pawnunits? + chess knowledge

Author: James Swafford

Date: 14:33:02 10/25/02

Go up one level in this thread

```On October 25, 2002 at 15:55:55, Uri Blass wrote:

>On October 25, 2002 at 14:46:24, James Swafford wrote:
>
>>On October 25, 2002 at 14:29:59, Uri Blass wrote:
>>
>>>On October 25, 2002 at 13:11:44, Robert Hyatt wrote:
>>>
>>>>On October 25, 2002 at 12:39:38, Ingo Lindam wrote:
>>>>
>>>>>Hello,
>>>>>
>>>>>I repost my former post under this new title just hoping to encourage
>>>>>more people to join the discussion:
>>>>>
>>>>>I am new at the Computer-Chess Club and would like to discuss some
>>>>>suggestions for (a new generation of) chess knowledge using (and
>>>>>generating?) chess engines. During my time at the university and at my
>>>>>first job after making my exams in computer science I was involved in
>>>>>statistical speech/pattern recognition and machine translation. That
>>>>>might atleast a reason for some of my ideas.
>>>>>
>>>>>I am not sure whether these suggestions have never been made or just
>>>>>named to be impossible to implement. (I am sure they are not.)
>>>>>
>>>>>I would really like to see the computers measure a position rather in a
>>>>>set of probabilities e.g. (P+,P=), where
>>>>
>>>>
>>>>I think that if you look at what chess programs do, this is the essence of the
>>>>evaluation.  The larger the number, the greater the probability that side will
>>>>win.  The smaller the number, the greater the probability that side will lose.
>>>>Scores near zero imply draw, of course...
>>>
>>>Not exactly.
>>>
>>>You can translate pawn to expected result but not to probabilities.
>>
>>It is trivial to translate a pawn score to a probability of a win.
>
>No it is not trivial.
>
>If the score is 0.00 what does it mean?

It means the position can be considered a draw.
Somehow potential has to be taken into account.

>
>Does it mean that you are sure of a draw or does it mean that both side have 50%
>chances to win?
>
>Can you translate?
>
>>Any number of functions in which the two are directly related may
>>be picked.  Obviously, some are better than others.
>>
>>
>>>
>>>The expected result is the same in the following 2 cases:
>>>probability 1% win for white and 98% draw
>>>probability 40% win for white and 20% draw.
>>>
>>>The probabilities are not the same.
>>
>>So?  That just means the pawn scores shouldn't be the
>>same, either.
>
>In both cases the expected result is 50% but in the first case you are almost
>sure about a draw when in the second case the position is less clear and both
>sides have good chances to win.
>

I would rather be in a position in which I still have a chance
to win, so I would score it higher than the almost certain draw.

>Uri

```