interval cost efficiency measure in dea-r

In real-life issues, we often face cases where data are not exactly known. dueto the importance of uncertain problems, this paper is devoted to providing models forevaluating dmus with interval data. two models are developed to obtain the lowerbound and upper bound for the cost efficiency measure in dea-r. by using theproposed models, some of the important type of experts' opinions can easily beincorporated within the dea cost efficiency models with interval data. a numericalexample is designed to illustrate the interval measure of the dea-r cost efficiencyscore.