A new Network DEA model

In recent years, there have been various researches which handle network systems in DEA literature. Network systems are the systems which consume some inputs to produce some outputs which some of them in some processes are used as the inputs of some of the other processes (intermediate products) to produce the final outputs. Most of the current approaches did not have any specified model for all the cases of network systems. In this paper a brief review of Kao approach is given and a new model for network systems will be presented which computes efficiency measure for all the cases of network systems