Evaluating the performance and classifying the interval data in data envelopment analysis

Standard Data Envelopment Analysis (DEA) supposes that the performance measure status from the point of view of input or output is known. Nevertheless, in some situations, determining the status of a performance measure is not easy. Measures with unknown status of input /output are called flexible measures. Moreover, traditional DEA models do not deal with imprecise data and assume that all input and output are exactly known. This paper proposes methods to evaluate efficiency and to classify data where the inputs and outputs of decision making units are known to lie within a bounded interval and where flexible measures exist. A sample of bank branches is used to illustrate the application of the proposed models.