  From a theoretical view, this paper addresses the general problem of
designing ordinal classification methods based on comparing actions with subset
of actions, which are representative of their classes (categories). The basic
demand of the proposal consists in setting a relational system (D, S), where S
is a reflexive relation compatible with the preferential order of the set of
classes, and D is a transitive relation such that D is a subset of S. Different
ordinal classification methods can be derived from diverse model of preferences
fulfilling the basic conditions on S and D. Two complementary assignment
procedures compose each method, which correspond through the transposition
operation and should be used complementarily. The methods work under relatively
slight conditions on the representative actions and satisfy several fundamental
properties. ELECTRE TRI-nC, INTERCLASS-nC, and the hierarchical ELECTRE TRI-nC
with interacting criteria, can be considered as particular cases of this
general framework.
