Data Envelopment Analysis And Malmquist Methods Based Research On Safety Efficiency Of Chinese Coal Mine Industry

Abstract:China is among one of the countries in the world with the highest safety accident rate (SAR) and death rate per million ton (DRPMT) in the coal mine industry. Safety efficiency assessment is the very prerequisite of ensuring the safety of coal mining, which is of great importance for safe production of the coal mine industry.In this paper, a study was made concerning the general safety situation of Chinese coal mine industry, based upon which obstacles standing in the way of safety efficiency improvement were pointed out.36out of the100top Chinese coal mine companies were chosen as the subject. The Person correlation test was conducted to select7variables concerning input and output as the sample data for safety efficiency assessment. The data envelopment analysis (DEA) method was then used to statically assess and analyze the sample data to decide the safety efficiency of these36coal mine companies from2005to2011. A projection analysis was also made upon companies that failed the safety efficiency analysis. After the projection analysis, the Malmquist exponential method was applied to dynamically assess and evaluate the sample data. During this assessment and evaluation, the safety efficiency variation exponent was decomposed into the technological progress variation exponent, the pure technology utilization efficiency variation exponent and the scale efficiency variation exponent.Static analysis of safety efficiency of the said36coal mine companies reveals the fact that safety efficiency of Chinese coal mine industry is at a relatively low level, with an average ranging from0.53to0.77. The main problems found include low technological and scale efficiency and huge differences among coal mine companies in terms of safety efficiency. Despite of a stable trend of coal mine company development, there is still great promise for safety efficiency improvement. The DEA analysis contributed to the ranking of the said36companies in terms of safety efficiency. Projection analysis of coal mine companies within the36ones that failed the DEA analysis showed redundancy of all input variables with ranging degrees. It was also found that all the input output ratios studied lagged behind the ideal standard.Dynamic analysis of safety efficiency showed that technological progress contributed to the safety efficiency improvement of coal mine industry. While the stagnant technology utilization efficiency failed to play its due part, and it was found to be the main obstacle standing in the way of safety efficiency improvement. It was also found that during the period from2005to2011, little had changed concerning the scale efficiency of Chinese coal mine industry.In the concluding part, countermeasures and suggestions were put forward from the perspectives of both the government and the coal mine company to address problems found during the DEA and Malmquist methods based safety efficiency assessment and analysis of Chinese coal mine industry.