a mixed-integer programming model for performance analysis of units with interval scale data

Data envelopment analysis (dea) is a mathematical programming-based technique for evaluating a set of homogeneous decision making units with multiple inputs and multiple outputs. one of the critical assumption when implementing the dea approach is that all variables are measured in a ratio-scale. in case, some of the input and / or output variables are measured on an interval scale, the basic dea models are useless or may produce meaningless results. in this paper, we propose an approach for assessing the efficiency and in-efficiency of units with interval scale data.