A fully fuzzy approach to data envelopment analysis

Data envelopment analysis (DEA) is a method to evaluate the efficiency of some decision making units which by using one or more inputs will make one or more outputs. In real world, most of the problems don’t have a certain mode. Fuzzy theory is one of the ways of considering uncertainty in the mathematical programming problems. In this study by using this idea, the DEA model on a fully fuzzy mode is proposed. The feature of this proposed model is that it considers 3 situations for problem and solving them simultaneously. The first situation occurs on a desired condition with the highest output and lowest input. The second is made of centric point of inputs and outputs and is analogous with the first condition. The third or undesired situation is when there are upper bound of input and lower bound of output. Results showed that the highest efficiency of some units is 1, so these units are efficient. To collate the efficient units on the proposed method, we can use the obtained centric points for efficiency of units.