Two-stage data envelopment analysis with imprecise data

Data Envelopment Analysis (DEA) has been recognized as an excellent method for analyzing performance and modelling organizations and operational processes, particularly when market prices are unavailable. In some situations (in real applications) of DEA applications, there are Decision Making Units (DMUs) which have two-stage structure. In the previous two-stage models have been assumed that all inputs and outputs of DMUs are exactly known and this assumption may not be true however (i.e. some or all of inputs and outputs may be imprecise). This paper proposes a method to determine efficiency of two-stage DMUs with Bounded inputs and outputs and extend the proposed method to deal with the more general case of imprecise data, that is mixtures of interval and ordinal data together with exact data.