THE FDH ESTIMATOR FOR PRODUCTIVITY EFFICIENCY SCORES
研究了自由处置壳（FDH）作为生产集非参数估计量的随机性质，指出其效率得分是随机变量，为正确使用该方法提供了理论依据。
In productivity analysis, the free disposal hull (FDH) is a nonparametric estimator for the production set, the set of inputs and outputs that are technically feasible. It is defined as the smallest free disposal set containing all observations in a sample of production units. One can then derive the production frontier and efficiency scores from the FDH. In the literature the method is used as if the FDH estimator were the true feasible set. However, assuming that individuals are drawn independently from a distribution where the support is the true production set, FDH efficiency scores are random variables. This paper investigates its stochastic properties.