Knowledge Dependency in Expanded Incomplete Information Systems

Incomplete information systems are expanded with the significance of objects in order to combine factors such as decision maker’s preferences and prior domain knowledge, etc. In the expanded incomplete information systems, information granules have their own significance, some basic concepts in rough set theory such as accuracy measure, rough entropies of knowledge and a set are both established and proved to be monotonous. Weightily, the concepts of knowledge dependency and knowledge dependency for decision are not only established but also deeply investigated. Furthermore, the measurement of knowledge dependency is described by mathematical formula strictly, some interesting results about the measurement of knowledge dependency are gained with the changing of knowledge.