Document Type : Research Paper
Department of Mathematics, Shabestar Branch, Islamic Azad University, Shabestar, Iran.
The performance of a decision making unit (DMU) can be evaluated in either across-sectional or a time-series manner, and data envelopment analysis (DEA) is a useful method for both types of evaluation. The Malmquist productivity index (MPI) evaluates the change in efficiency of a DMU between two time periods. It is defined as the product of the Catch-up and Frontier-shift terms. In this paper, we study the Malmquist productivity index of a DMU between several time periods.