Ghasem Tohidi - Department of Mathematics, Central Branch, Islamic Azad University, Tehran, Iran
Hamed Taherzadeh - Department of Mathematics, Central Branch, Islamic Azad University, Tehran, Iran

In the real world, there are many applications which some inputs and outputs have sum-fixed value. This paper develops a DEA (data envelopment analysis) model to accommodate competition over outputs and inputs. In the proposed model, the total output and inputs of all decision making units (DMUs) over some special outputs or inputs is fixed, and DMUs compete with each other to maximize their self-rated DEA efficiency score.

Data envelopment analysis (DEA), Efficiency evaluation, Competition, Fixed-sum output. Fixed sum inputs