p.29 Such a method [method by which various averaged out weights of positional parameters are introduced
A.K.] of deriving a positional estimate in chess is wrong. A positional factor that yields a positive result in one
situation may yield a negative result in another. For instance, are doubled pawns good or bad? The answer depends on the situation.
Sometimes doubled pawns are a suitable target for an attack, since one of them cannot support the other. But sometimes doubled
pawns contribute to the control of a square through which important communication lines (trajectories of pieces) pass, and
then the doubling is extremely useful. the same thing may be said of other factors entering into the positional component
of Shannon's prototypical scoring function.
In the chess program under consideration, a quite different decision was made about the positional
component of the scoring function, basing it on the control of those squares making up the trajectories that enter the MM.
The side controlling the larger number of squares has a positional preponderance [quoted in Selected Topics
in Indeterministic Systems p.147]
p.38 Control of fields does not mean control of the whole board, but control of only those fields
that may be used in the impending play. Therefore one must strive for control of the field consisting of those trajectories
in which the pieces can move, but have not moved yet.
At the node in the search tree where we find ourselves at a given moment, we must unravel
all those sheaves of trajectories which have not yet been developed and determine which player has control of the majority
of the fields consisting of the trajectories not yet used in the play. This allows us to forecast the result of the play
-- the result of a search which, in particular, had to be renounced at the terminal nodes of the variations for lack of resources
[quoted in Selected Topics in Indeterministic Systems p.147]
p.144 positional value represents a ratio Kw / Kb where Kw and Kb is the number of squares in the
trajectory controlled by white and black respectively. [cited in Selected Topics in Indeterministic Systems, p.158]
p.146 [although this page could refer to a footnote] When a chess master plays a game he uses historical
experience (his own and the experience of others) in four different ways:
1. In parrot fashion. This is characteristic of the opening. The theory of the opening is not subject to
judgment in any of its parts, and the master makes his moves in the opening without inserting himself into the process, i.e.,
he moves as a parrot talks.
2. By the handbook method. In playing a game, the master seeks out, in his store of accumulated knowledge,
the exact position occurring in the search. This library position has a score; since the positions coincide, the score of
the variation is known, and the variation itself may be cut off. This usage of historical experience is characteristic of
the endgame, but may be successful in the opening as well, when moves are transposed.
3. By the outreach method. This is based on an attempt to reach positions that the handbook method can use.
The master looks up library positions having a favorable outcome and resembling the search position. (See the Glossary of
Terms for a definition of nearness.) Having found such positions, the master constructs his search so as to get them into
the search tree if possible. Then he relies on method 2. Therefore this method is also characteristic of the endgame and,
perhaps, of the opening.
4. By the associative method. This is based on the partial congruence of the position in the search with
positions in the library. The master seeks out a fragment of a library position, i.e., a small group of pieces whose action
has led to success. If the search position contains the same group of pieces in the same constellation, he includes the group
in his search, in order to see whether it will lead to success in the current case. If the fragment has often been successful
in the past, it is apt to succeed again. This method determines a direction for the search and on the average it saves resources
while the search is under construction. It would appear the at associative method presents the only
way to apply historical experience to the middle game and to complex endgames.[quoted in Selected Topics in Indeterministic
Systems, p.175]
