An approach to covering-based rough sets through bipartite graphs

Covering is an important form of data, and covering-based rough sets provide an effective tool to deal with this data. In this paper, we use bipartite graphs to study covering-based rough sets. Firstly, a bipartite graph is constructed through a covering, named bipartite graph associated with a covering. According to a bipartite graph associated with a covering, two equivalent representations of a pair of covering approximation operators are presented. Then, some properties of this pair of covering approximation operators and reducible elements in a covering are investigated through the constructed bipartite graph. In a word, these results show an interesting view of graphs to investigate covering-based rough sets.