网络DEA模型研究多个进程和多个子系统的复杂系统的效率度量.针对中间产出无法为第2阶段完全消耗的情形,传统DEA模型对系统效率的评价偏高,已有网络DEA模型则对系统效率的评价偏低.本文提出部分中间产出作为最终产品,进入流通渠道的两阶段效率模型,用来测度两阶段生产过程的真实效率.采用乘积形式描述两阶段合作的特征,给出不同阶段效率的上下界,并将某个阶段效率作为参数,将非线性效率模型转变成线性规划模型.数值分析验证了新方法的有效性和可行性.
Network DEA models have been widely used in dealing with performance measurement of complex organizations and systems with multiple processes and multiple sub-systems.In real situations where intermediate products produced by first stage can not be consumed completely by second stage,traditional DEA models overvalues system efficiency while current network DEA models underestimate system efficiency.This paper put forwords two-stage efficiency models,where part of the intermediate products are viewed as final products and entered into distribution channels,and depicts real performance of two-stage production process.This paper provides product forms to characterize cooperation of the two stages and discusses both upper and lower efficiency bounds of various stages.A linear programming model is converted from non-linear efficiency model by considering one of the efficiencies of the stages as a parameter.The model is illustrated by a numerical evaluation of the bank's performance.