MMN-2891
Approximation lattices defined by tolerances induced by irredundant coverings
D. Gégény; I. Piller;Abstract
The topic of rough set theory considers a relation to determine the lower and upper approximations of a set $X$. Originally, this relation was assumed to be an equivalence relation. This research focuses on using tolerance relations instead of equivalences, i.e. we do not assume the transitivity of the relations. More specifically, in this paper we investigate tolerances induced by irredundant coverings. We characterize the interrelation between the lattices of lower and upper approximations of such tolerances $R$ and $\rho$. The theory of Formal Concept Analysis makes it possible to examine the inclusions of the resulting concepts. We also use quasiorders (denoted by $\trianglelefteq(\rho)$ and $\trianglerighteq(\rho)$) and an equivalence relation (denoted by ker $\rho$) for summarizing the connection between tolerances and lattices in a theorem.
Vol. 20 (2019), No. 1, pp. 245-254
DOI: 10.18514/MMN.2019.2891