Mohammad Taghavi - Department of Mathematics, University of Sistan and Balochestan, Zahedan, Iran
Faranak Hosseinzadeh saljooghi - Department of Mathematics, University of Sistan and Balochestan, Zahedan, Iran

In this paper a model is introduced to evaluate decision making units (DMUs) in the production possibility set (PPS), with three properties. Then we studied effect of imprecise data in the convex hull of DMUs model (CHD). We analysed efficiency frontier in CHD model with imprecise data. We applied first method and second method in CHD model for interval data. Finally, an example presented to be analyzing CHD model with interval data. In this example efficiency is calculated on the convex hull with first method and second method.

Data envelopment analysis, Convex hull, efficient frontier, interval data, interval efficiency