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Material Value

The final group of advisors are used for assigning a fixed material value to each type of piece, which is later awarded to a player for each piece of that type he owns in a given position. This value is a weighted sum of the values returned by the advisors listed in this section, and does not depend on the position of the piece or of the other pieces on the board. Note that white king and black king are viewed as different types of pieces during the computations below.

max-static-mob:The maximum static-mobility for this piece over all board squares.

avg-static-mob:The average static-mobility for this piece over all board squares.

max-eventual-mob:The maximum eventual-mobility for this piece over all board squares.

avg-eventual-mob:The average eventual-mobility for this piece over all board squares.

eradicate:Awards 1 point for each opponent goal to eradicate pieces which match this type, and minus one point for each player goal to eradicate our own piece matching this type.

victims:Awards 1 point for each type of piece this piece has a power to capture (i.e. the number of pieces matching one of its capture-types). A bonus is provided for the effects of each capture, as discussed for the local-threat advisor above. It would be interesting to have a dynamic version of this which gave preference to pieces which could capture other pieces actually present in a given position.

immunity:Awards 1 point for each type of enemy piece that cannot capture this piece.

giveaway:Awards 1 point for each type of friendly piece that can capture this piece.

stalemate:This views the goal to stalemate a player as if it were a goal to eradicate all of the player's pieces, and performs the same computation as eradicate above.

arrive:Awards a piece 1 point if the player has an arrival goal predicated on that type of piece. It awards points if the piece can promote to an arrival-goal piece in promotions. Values are negated for opponent arrival goals.

promote:This is computed in a separate pass after all the other material values. It awards a piece a fraction of the material value (computed so far) of each piece it can promote into. This advisor is not fully implemented yet, and was not used in the work discussed in this paper.

Section 3 provides concrete examples of the application of these advisors to the rules different games discussed in this thesis.