Knowledge Approximation and Rule Acquisition Based on VPRS in Ordered Information Systems

This paper deals with the knowledge approximation and rule acquisition based on variable precision rough sets in ordered information systems. The concepts of upward ß-lower approximation, upward ß-upper approximation, downward ß-lower approximation and downward ß-upper approximation based on dominance relation are introduced, and an approach to rule acquisition is also proposed in ordered decision tables with an illustrative example.