Alternative technical efficiency measures: Skew, bias and scale
在固定效应随机前沿模型中，本文提出以样本中最差企业为基准的新效率度量，相比传统以最佳企业为基准的度量，当样本中接近前沿的企业较多时偏差更小，并进一步提出同时考虑最佳和最差企业的双侧度量。模拟表明，新度量在特定偏度和效率差异规模下更优。
SUMMARY In the fixed‐effects stochastic frontier model an efficiency measure relative to the best firm in the sample is universally employed. This paper considers a new measure relative to the worst firm in the sample. We find that estimates of this measure have smaller bias than those of the traditional measure when the sample consists of many firms near the efficient frontier. Moreover, a two‐sided measure relative to both the best and the worst firms is proposed. Simulations suggest that the new measures may be preferred depending on the skewness of the inefficiency distribution and the scale of efficiency differences. Copyright © 2010 John Wiley & Sons, Ltd.