Sepideh Vatani - Department of Mathematics, Science and Research Branch, Islamic Azad University,Tehran,Iran
Mohsen Rostamy-Malkhalifeh - Department of Mathematics, Science and Research Branch, Islamic Azad University,Tehran,Iran

Data Envelopment Analysis (DEA) is a linear programming based method to measure performance a group of homogeneous decision making units (DMUs) units such as firms with multiple inputs and outputs. In two-stage unit all or part of the outputs of the first stage are assumed to be the second stage s inputs and measuring performance of these DMUs is one of the important issues in DEA. There are two ways, multiplier or additive model, to calculate efficiency of DMU in DEA which in this paper, a new model is proposed by using multiplier method to evaluate efficiency of such unit then according to the presented model, the efficiency of a hose and plastic product manufacturer in 10 years is examined

Data Envelopment Analysis (DEA); Efficiency; Two-Stage Unit; Undesirable and Desirable Outputs; Multiplier Model.