Evolution Characters of China's Cities Based on The Super-efficient DEA
本文用超效率DEA模型评估中国15个副省级城市的效率，发现效率值呈倒U型变化且有收敛趋势，效率值大于1的城市逐年增多。
This paper has set up the input-output evaluation index system of China's 15 sub-provincial cities based on the efficiency. The simple model of DEA,such as C2R and BC2 model,are compared with super-efficiency model of DEA first in this paper,and then 15 sub-provincial cities in China are evaluated by the three models. The results indicate that super-efficiency model of DEA has advantages in the use.The evolution characteristic of 15 sub-provincial cities' efficiency are conclused that:firstly,the changes of super-efficient DEA value are inverted-U and the value has trend of convergence; secondly,The number of cities,which the value of super-efficient DEA is greater than 1,are increasing year by year; thirdly,the overall super-efficient DEA values are changing relatively stable,but some of them are changing dramatically.