Set Approximations in Multi-level Conceptual Data

摘要

In this paper, two kinds of multi-level formal concepts are discussed. Based on the proposed Multi-level formal concepts, we present two pairs of rough set approximations within fuzzy formal contexts. By the proposed rough set approximations, we not only approximate a crisp set, but also approximate a fuzzy set with the multi-level concepts. We discuss the properties of the proposed two pairs of approximation operators in details.