Two-stage data envelopment analysis with interval data

Traditional DEA models deal with measurements of performance of operational units regarding multiple inputs and outputs. Recently, DEA has been extended to examine the efficiency of two-stage processes where all the outputs from the first stage are inputs to the second stage. This application of DEA requires that the values for all inputs and outputs be known exactly. The current paper, develops the usual two-stage DEA structure to one that determines the performance of two-stage production processes with interval data. In the proposed approach, the intermediate measures are flexible and their input/output status will be determined