Rule Induction Algorithm Based on Rough Sets for Incomplete Information System

In this paper, the concept of non-symmetric similarity relation had been used to formulate a new definition of approximation to an incomplete information system. By means of the new definition of approximation to an object set and the concept of attribute value pair, the rough-sets-based methodology for certain rule acquisition in an incomplete information system had been developed. The algorithm could deal with incomplete data directly and do not required changing the size of the original incomplete system. The experiment showed that the algorithm provides precise and simple certain decision rules and does not affected by the missing values.