A SIMPLE CHARACTERIZATION OF RETURNS TO SCALE IN DEA

In this paper, we will present a simple method for deciding the local returns-to-scale character- istics of DMus (Decision Making Units) in Data Envelopment Analysis. This method proceeds as follows: first, we solve the BCC (Banker-Charnes-Cooper) model and find the returns-to-scale of BCC-efficient DMus and a' reference set to each BCC-inefficient DMU. We can then decide the local returns-to-scale characteristics of each BCC-inefficient DMU by observing only the returns-to-scale characteristics of DMus in their respective reference sets. No extra computation is required. We can apply this method to the output-oriented model and to the additive model as well.,