An incremental approach to attribute reduction of dynamic set-valued information systems

Set-valued information systems are important generalizations of single-valued information systems. In this paper, three relations are proposed for attribute reduction of set-valued information systems. Then, we convert a large-scale set-valued information system into a smaller relation information system. An incremental algorithm is designed to compress dynamic set-valued information systems. Concretely, we mainly address the compression updating from three aspects: variations of attribute set, immigration and emigration of objects and alterations of attribute values. Finally, several illustrative examples are employed to demonstrate that attribute reduction of dynamic set-valued information systems are simplified significantly by our proposed approaches.