Query Answering in DAKS Based on Reducts

In this paper we are interested in necessary and sufficient conditions needed to learn definitions of non-local attributes in DAKS (see [15], [1.4]) assuming that the confidence of what we learn is kept possibly the highest. The notion of a reduci introduced in Rough Sets theory seems to be quite useful in solving this problem. For every non-local attribute a and local attributes A, we introduce the notion of -directed set of reducts which basically models the strategy of search for a definition of a in DAKS.