A Mathematical Model for Dynamic Efficiency Using Desirable and Undesirable Input-Output

Abstract Present models of Data Envelopment Analysis (DEA) depend on static productions (independent of time) which can easily lead to erroneous appraisal results due to incorrect hypothesis, since in the real world we encounter such situations where inputoutput levels are time-dependent like capital stock which are effective on the output levels during the production periods. Such units cannot be evaluated by the classic or static DEA. In this paper, a model will be proposed for evaluating relative efficiency of units which have time-dependent input-output. Occasionally the Decision Making Units (DMU) might, in addition to using and producing desirable input-output, use and produce undesirable input-output as well. Segregation of desirable and undesirable components from each other in the input vector, and also in the output vector as well as study of these factors is a crucial issue which causes improvement of the operational trend and increased efficiency of the units. Also in this paper, efficiency measuring in presence of desirable and undesirable factors, in the dynamic state has been studied