A Review of Measuring Inefficiency Models

An inefficient firm causes a waste of resources by using a non-optimal combination of capital and labor and especially energy. Measuring inefficiency and identifying the factors that cause it is vital in achieving the firm's potential production and, as a result, the sustainability of economic growth and increasing the economic well-being of the society. Meanwhile, choosing the right model to measure inefficiency is always one of the basic challenges among researchers in this field. This study attempts to provide an overview of the concept of efficiency and its types and different measurement models with an emphasis on the Frontier Analysis. Considering the large volume of theoretical and experimental studies in inefficiency, our review aims to provide a proper understanding of their strengths and weaknesses by investigating the evolution of the models demonstrated in the literature, and thus helps the researcher to create a clear framework for analysis and choosing the appropriate model. Furthermore, this study offers suggestions to measure inefficiency as accurately as possible from the theoretical and technical viewpoints, which have been understudied in the literature.