Labor Efficiency Evaluation in Chinese Coal Enterprise: Using the Hybrid DEA Model with Undesirable Output

Coal industry is an important pillar of China's economic development. The level of labor productivity has an important influence on coal mining. In this paper, Hybrid-DEA model is used to evaluate labor productivity and relative gas emission is taken as an undesirable output into the factors affecting labor productivity. Based on the statistical data of a large coal enterprise in China from 2015 to 2017, this paper makes an empirical analysis of the labor productivity in the production process of a coal enterprise from the micro level, which provides decision-making basis for the production management of a coal enterprise. The study shows that there is much room for improvement in the labor productivity in most of the mining areas of the coal enterprise, and the labor productivity in more than half of the mining areas continues to decline. Wilcoxon test method is adopted to analyze the comprehensive efficiency and key improvement indicators of labor productivity from the perspective of the mining area located in the urban or suburban areas. The results show that there are significant differences in comprehensive efficiency and production cost between the two groups. The comprehensive efficiency and key indexes of the suburban mining areas are better than those of the urban mining areas.