Journal of Operational Research and Its Applications ( Applied Mathematics ) - Lahijan Azad University

In traditional DEA models, one faces the challenge of zero and unequal weights for evaluating each decision-making unit (DMU). On the other hand, for measuring the efficiency in these models, the system is considered as a black box, disregarding its internal processes. One of the strategies applied to deal with this problem is to use common weights of each input/output in all DMUs. In practice, most decision-making units evaluated together include internal processes with different structures, referred to as network structure. Similar to the traditional DEA models, a challenge exists for the network structures. In a number of cases, common weight sets in two-stage network structure have been proposed that do not include network general structures. This paper aims at proposing the same challenge for network general structures to solve the problem of network general structures through a newly proposed model of common weights set. The models are applied on kao’s examples to illustrate the results.