Investigating the Effect of Congestion in Undesirable Outputs Using Data Envelopment Analysis Case study: performance Assessment of University

The aim of this paper is to investigate congestion in undesirable outputs. The measurement of congestion is important for performance evaluation. In order to calculate the performance and allocate resources well، it is necessary to measure congestion. Data Envelopment Analysis (DEA) is one of the most appropriate tools for measuring performance. Many researchers have studied this topic by means of DEA. Inefficiency is a necessary condition for the existence of congestion. The managerial issue is defined as “evidence of congestion presents when increase in one input or more can be associated with decrease in one output or more، without worsening any other input or output or proceeding in reverse. However، in the scenario where desirable and undesirable outputs both exist، the definition of congestion is different because the desirable outputs are expected to be more، while the undesirable outputs are expected to be less. Therefore، we cannot apply the current theories and definitions directly for measuring congestion. The previous studies only pay attention to the framework of desirable outputs. In fact، undesirable outputs often accompany desirable outputs in production and services. In this study، a new approach for measuring congestion with undesirable outputs is proposed and applied to analyze congestion of the undesirable outputs and inputs in a department of university. The results indicate that all of inefficient departments that have congestion in undesirable output and also، particular congestion in undesirable outputs has the highest correlation with the efficiency.