A super-efficiency model based on improved outputs in data envelopment analysis

This paper addresses "super-efficiency" issue based on improved outputs. Although the method is similar to an outputoriented version of Andersen and Petersen's model [P. Andersen, N.C. Petersen, A procedure for ranking efficient units in data envelopment analysis, Management Science 39 (10) (1993) 1261-1264] (called AP model) under variable returns to scale, it is not limited to use the input amounts of evaluating DMU, therefore, it differs from AP approach. We can obtain a total ordering of DMUs by using this method. The proposed method will be particularly useful when getting an input combination for improving outputs is suitable for decision makers. (c) 2006 Elsevier Inc. All rights reserved.