Alireza Amirteimoori - Department of Applied Mathematics, Islamic Azad University, Rasht, Iran
Sohrab Kordrostami - Department of Applied Mathematics, Islamic Azad University, Lahijan, Iran
Zahra Bakhoda - Department of Applied Mathematics, Islamic Azad University, Lahijan, Iran

In real world, there are systems which are composed of independent production units. They use different inputs to produce outputs. This paper, develops a DEA-based model by considering the production possibility set (PPS) under the variable returns to scale (VRS) assumptions, and we will provide a model that focuses on the calculating the efficiency of the whole system along with the efficiencies of its components, and takes the operations of individual components into account indetermining the efficiency of the whole system.

DEA, Parallel system, Efficiency decomposition