A new model for calculating the efficiency of existing cement companies with a network structure (an application of data envelopment analysis)

The purpose of this paper is to present a new model of data envelopment analysis with network structure to evaluate the performance of Tehran cement companies. For this purpose, cement companies listed on the stock exchange during the years 93-95 were evaluated. The results showed that the new model can evaluate the performance of these factories - which have a network structure and include multiple indicators - and, in addition to commonly used financial and technical indicators, to consider undesirable outcomes and sustainability criteria in the supply network. Meanwhile, the mindset of decision makers about the preferential importance of some indicators relative to each other is also considered in the form of weight constraints to bring the efficiency closer to the real value. According to the results, the factories are divided into two categories: efficient and inefficient. Based on this new model, only 7 cement supply companies have been able to achieve efficiency within the three surveyed periods of the 42 listed companies.