Robust elements in rough set abstractions

Abstract

In [3] the classical rough set approach was generalized in the manner that lower and upper approximations were replaced by arbitrary kernel and closure operators respectively. Furthermore, the resulting lattices of rough set abstractions were described as P-products. This approach, though promising, needs additional research to become part of a unifying theory of Rough Set Theory and Formal Concept Analysis. For example, the role of robust elements and the possible existence of suitable negation operators were not addressed. We present results in these directions and on the structure of these lattices. © Springer-Verlag Berlin Heidelberg 2009.