6 Conclusions
Knowledge reduction of dynamic covering information systems is a significant challenge of coveringbased rough sets. In this paper, firstly, we have analyzed the related families-based mechanisms of constructing attribute reducts of dynamic covering decision information systems with variations of attributes and employed examples to illustrate how to compute attribute reducts of dynamic covering decision information systems when varying attribute sets. Secondly, we have presented the related families-based heuristic algorithms for computing attribute reducts of dynamic covering decision information systems with attribute arriving and leaving and employed examples to demonstrate how to update attribute reducts with the heuristic algorithms. Finally, we have employed the experimental results to illustrate that the related families-based incremental approaches are effective and feasible for attribute reduction of dynamic covering decision information systems.
In the future, we will study knowledge reduction of dynamic covering decision information systems with variations of object sets. Especially, we will provide effective algorithms for knowledge reduction of dynamic covering decision information systems when object sets are varying with time.