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

Author: Bob Durrett

Date: 12:55:30 10/26/02

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On October 25, 2002 at 19:50:05, Ingo Lindam wrote:

>On October 25, 2002 at 13:14:28, Josť Carlos wrote:
>>  Sounds interesting, but a real example (even if it is simple) would help. The
>>idea alone is not useful, and has been suggested in the past.
>>  Josť C.
>Hello Jose,
>two very very very simple patterns might be
>(P+,P=,P-)(Pe4,Pg4,Nf5,pe5,pg5) = (0.5,0.3,0.2)
>(P+,P=,P-)(Pf3,Pg4,Nh2,pg5)     = (0.2,0.29,0.51)
>these are just two as I said very very simple pattern you might derive or
>"check" by your chessbase.
>Best regards,

These are my "post-breakfast" thoughts.  Again, I am still trying to see whether
or not I understand what you are proposing.

Since the chess engine must find a move, we need to think about how that would
be done using your "patterns."  Please ignore the trivial case of getting the
move from an opening book or an endgame tablebase.  Let's limit ourselves to the

Associated with each of the patterns you store in your computer [regardless of
storage medium], there typically will be moves associated with that pattern.
For example, if the pattern is the one associated with the thematic sac of a
bishop on h7, then the bishop move Bxh7 could be the one associated with that
pattern.  Some patterns may have more than one move associated with it.  One
could generalize to include "combinations" assiciated with certain positions.
For example, recall the familiar smothered mate involving the moves Nf7+,
Kh8-g8, Nh6 dis. ch. [with the queen on the diagonal], Kh8, Qh8+ RxQ Nf7
smothered mate.  This is a case of a combination being associated with the
position fragment [which you call a "pattern."]

Typically, a position occuring in a game [being played with the chess engine]
may include dozens or even hundreds of position fragments for which you have
patterns in your database [or table].

In a parallel processing [or hybrid] implementation of your concept, there would
be some process required to go from the information you have for the relevant
patterns to the choice of move.

The various relevant patterns may each have one or more moves associated with
it.  Each such move could be considered to be a probability function of the
pattern.  P[move1] = etc.

How do you decide which pattern should be taken more seriously?

If there are hundreds of patterns in the position, there could easily be
hundreds of moves, each associated with one or more of the patterns.  Somehow,
you must decide how to arrive at the one and only one move to play.  I must
admit that this is unclear to me at this time.

Am I still on track?

Bob D.

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