ideal and anti-ideal decision making units: a fuzzy dea approach

in this paper, by introducing two virtual decision-making units (dmus) called ideal dmu (idmu) and anti-ideal dmu (admu) with fuzzy inputs-outputs, the efficiency evaluation of dmus are done by fuzzy data envelopment analysis (fdea). therefore, we evaluate dmus from the perspective of the best and worst possible relative efficiency. for each dmu two efficiencies are calculated while inputs and outputs are fuzzy. these two distinctive efficiencies are combined with the closeness coefficient (cc) index. the cc index is then used for an overall ranking of all dmus. finally, we compare the result of proposed fuzzy dea model with león et al.’s (2003) results by representing a numerical example.