Patent ID: 7720785

Claim:
A system for classifying data from a data stream comprising at least one drifting concept, the system comprising: a dynamic rule classifier including: a window for viewing a plurality of records of the data stream; a plurality of rules wherein each rule is derived from the plurality of records appearing in the window; at least one data tree for maintaining the plurality of rules; and, an engine for evaluating the plurality of records against the plurality of rules, detecting a concept drift in the data stream, invoking at least one algorithm for deriving at least one new rule and updating the plurality of rules wherein detecting a concept drift includes determining if a difference between the number of misclassified records N ij in a current window W i and the number of misclassified records N kj in a reference window W k reaches a user-defined threshold minWR wherein invoking at least one algorithm for deriving at least one new rule includes computing the number of misclassified records N ij in the current window W i , where N ij =N i−,j +g ( r i+w−1 , i, j )− g ( r i−1 , i, j ) where g(r, I, j)=1 if the true label for the record r is C j and the record r is misclassified by C i as some other class C x , and g(r, I, j) =0 otherwise.