关键词: 时滞性, 两阶段数据包络分析（DEA）, Malmquist生产率指数

Abstract: Conventional DEA models assume that the inputs of a specific period are consumed to produce the outputs of the same period. This underlying assumption may not be valid in some performance evaluation, that outputs of a specific period can be thought to be produced by consumption of not only inputs in the same period but also the inputs in multiple previous periods. In order to evaluate the efficiency of two-stage processes more objectively, this paper proposes a two-stage DEA model which considers the output time-lag effects of intermediate variable. And it applies the Malmquist productivity index to know the dynamic changes of time series finally, so as to find out the reason of efficiency change. The proposed method is applied to evaluate the innovation efficiency of 30 provinces of China. The results show that the rank of considering the output time-lag effects of intermediate variable model is more objective, the efficiency of innovation is not only closely related to the efficiency of R&D stage and economic transformation stage, but also closely related to the influence of external factors.

Key words: 时滞性, 两阶段数据包络分析（DEA）, Malmquist生产率指数