Abstract
Decision-making process is to find the best option from all of the feasible alternatives. Considering the efficiency interval, efficiency scores from optimistic and pessimistic points of view, all the possible evaluations can be illustrated. Therefore, Interval DEA models can be helpful for a decision maker needs all those possible efficiency values that reflect different perspectives. The mentioned upper and lower bound of efficiency interval is obtained from the optimistic and pessimistic viewpoints. As a matter of fact, it can be propounded that in assessing DMUs considering the mere optimistic efficiency score is not a acceptable criterion for ranking units and performance evaluation of them. Since, in the event that an entity has gain a high efficiency with a great risk it will not certainly have priority to a unit with relatively balancing efficiency, suitable confidence interval and a low risk. In this paper considering the above issues a method for ranking units based on efficiency intervals is presented. With an application the clarity of the proposed procedure will be demonstrated.
Keywords: Data envelopment analysis, interval DEA models, ranking.
