关键词: 网络DEA , 整体效率 , 子阶段效率 , 关联指数

Abstract: Basing on the deeply analysis, we regard the banking business as a twostage network with intermediate input and output. The first subprocess is characterized by liabilities and intermediary business. The second subprocess is characterized by assets. Based on the network, we construct a network DEA model with intermediate input and output. Moreover, we prove that network efficiency is equivalent to substage efficiency, which means our model can reveal the inner structure of the black box. We also calculate the overall efficiency, substage efficiency and correlation index of 16 Chinese listed commercial banks from 2006 to 2010. The results show that stateowned commercial banks revealed obvious advantage in the liability and intermediate business. Jointstock commercial banks are most efficient in assets business. And city commercial banks have the lowest correlation index.

Key words: network DEA , overall efficiency , substage efficiency , correlation index