It is usual to rank the participating countries in the Olympic Games in accordance with the number of medals they have won. An alternative ranking is suggested in this paper. This ranking is based on each country’s ability to win medals in relation to its available resources. This is an efficiency that can be measured with the help of Data Envelopment Analysis (DEA) for which two models exist: ...

Most applications of data envelopment analysis (DEA) employ standard constant or variable returns-to-scale (CRS or VRS) models. In this paper we suggest that these models may sometimes underutilize our knowledge of the underlying production process. For example, in the context of higher education considered in the reported application, individual universities often maintain a certain student-to...

There are some specific features of the non-radial DEA (data envelopment analysis) models which cause some problems under the returns to scale measurement. In the scientific literature on DEA, some methods were suggested to deal with the returns to scale measurement in the non-radial DEA models. These methods are based on using Strong Complementary Slackness Conditions in the optimization theor...

This chapter discusses returns to scale (RTS) in data envelopment analysis (DEA). The BCC and CCR models are treated in input oriented forms while the multiplicative model is treated in output oriented form. (This distinction is not pertinent for the additive model which simultaneously maximizes outputs and minimizes inputs in the sense of a vector optimization.) Quantitative estimates in the f...

The present article attempts to investigate the validity of the Comanor–Wilson Minimum Efficient Size (MES) measure. The basic assumption is that firms that have exhausted scale economies are in non-increasing returns to scale. The same firms are also assumed to have a size greater than MES estimated on sales (total turnover), employment or fixed assets. Data Envelopment Analysis (DEA) is used,...

Traditional super-efficiency data envelopment analysis (DEA) models rank efficient units under the assumption of constant returns to scale (CRS). However, infeasibility may occur in super-efficiency models under variable returns to scale (VRS). This paper proposes a modified VRS super-efficiency DEA model to deal with infeasibility by relaxing the convexity constraint 1, 0 1 n j j j λ = ≠ = ∑ t...

This research identifies returns to scale (RTS) of efficient decision making units (DMUs) with desirable (good) and undesirable (bad) inputs and outputs by presenting a new DEA (data envelopment analysis) approach. In this study, we first introduce a new input-output oriented model to determine efficient DMUs in the presence of undesirable factors and then, returns to scale of these DMUs are es...