The researches on efficiency of listed electric power companies based on DEA

Efficiency evaluation is very important to the company's development. And compared with conventional methods, data envelopment analysis (DEA) shows several advantages. So, by applying DEA theory, the relative efficiency of twenty-three listed electric power companies has been analyzed in this paper. The results indicate that under constant returns-to-scale, only four companies are efficient and the remaining companies are inefficient. A further study shows that the inefficient companies are caused mainly by scale inefficiency. Therefore, the internal management should be strengthened and the structure of the resources should be optimized to improve the companies' efficiency.