A Theoretical Formulation of Object-Oriented Rough Set Models
We introduce object-oriented paradigm into rough set theory. First, we provide concepts of class, object, and name, respectively. Class structures represent abstract data forms, and abstract structural hierarchy based on is-a relationship and has-a relationship. Object structures illustrate many kinds of objects and actual dependence among objects by is-a relationship and has-a relationship. Name structures provide concrete design of objects, and connect class structures and object structures consistently. Next, combining class, name and object structures, we propose object-oriented information systems, which include “traditional” information systems as special cases. Moreover, we introduce indiscernibility relations on the set of objects, lower and upper approximations, and object-oriented rough sets in the object-oriented information systems.