Measuring the efficiency of grid companies in China: A bootstrapping non-parametric meta-frontier approach.

The unbundling policy reform of power industry has become a worldwide trend since 1980s. There are quite many studies focusing on the efficiency changes of transmission and distribution sectors in European and Latin American countries while few reports on China's issues have been found. This paper employs a nonparametric frontier estimation combined with meta-frontier and bootstrapping method to measure the productive efficiency and changes in the decomposition index for China's 31 grid companies from 2004 to 2013. In addition, it further employs Tobit regression model to analyze the influences of relevant policies and heterogeneity factors, such as natural conditions and economic development. The results indicate that the grouping approach extends the application of non-parametric data envelopment analysis, which may decrease the assumption of homogeneity for the decision making units and provide better efficiency estimates by increasing the credibility of the evaluation results. Overall productive efficiency increased during the whole study period, with technology progress the main contributor to this improvement. Efficiency trends fluctuated with changes in economic development and power supply situation, and the economics and customer density had positive effects on productive efficiency while the influence of clean power proportion is negative. [ABSTRACT FROM AUTHOR]