Maps between some different kinds of contraction function: The finite case

摘要: In some recent papers, the authors and Peter Gardenfors have defined studied two different kinds of formal operation, conceived as possible representations intuitive process contracting a theory to eliminate proposition. These are partial meet contraction (including limiting cases full maxichoice contraction) safe contraction. It is known, via representation theorem for former, that every operation over theory. The purpose present paper study relationship more finely, by seeking an explicit map between component orderings involved in each shown at least finite case suitable exists, with consequence relational, transitively antisymmetrically relational functions form identifiable subclasses functions, any modulo logical equivalence. constructing map, composition four simple transformations, mediating notions bottom top introduced. infinite remains open.