cost efficiency in two-stage fdh networks

A very important subject in data envelopment analysis (dea) involves performance assessment of airlines based on free disposal hull (fdh) models in pre- and post-flight stages. in this paper, we propose a cost efficiency model for iranian airlines under the framework of fdh-based two-stage processes with elimination of the convexity constraint. the proposed fdh-based cost efficiency model is technically a nonlinear programming problem that using pairwise comparison, can evaluate the decision-making units (dmus) through less calculations and determine the standard for inputs based on input prices. in a similar manner, we can arrive at the standard for outputs by considering the output prices. in the end, 13 iranian airlines are evaluated in a two-stage dea process with omission of the convexity constraint and their corresponding input and output standards are presented.