Matrix Algorithm for Attribute Reduction in Incomplete Information System

By analyzing attribute reduction based on tolerance matrix in incomplete information system,a new binary tolerance matrix under single condition attribute is defined.At the same time,absorption of operation rule between two of them is also defined.The binary tolerance matrix under the whole condition attributes is gained by that rule.If the binary tolerance matrix based on some of condition attributes is equal to the binary tolerance matrix under the whole condition attributes,those condition attributes make up of an attribute reduction.It is proved that the attribute reduction acquired from this new method is equivalent to it based on positive region in incomplete information system,and an algorithm for attribute reduction is presented.An example is used to illustrate the rationality of this new algorithm.