Data envelopment analysis was introduced as a nonparametric linear programming estimator to estimate the production frontier and technical efficiency of observed production units. Allowing multiple inputs and multiple outputs, the approach can be considered a nonparametric quantile regression...

In efficiency studies using the stochastic frontier approach, the main focus is to explain inefficiency in terms of some exogenous variables and computation of marginal effects of each of these determinants. Although inefficiency is estimated by its mean conditional on the composed error term...