Study of the Relationship between Concentration, Skilled Labor and Efficiency Using the Fuzzy Logic Approach in Iranian Manufacturing Industries

Document Type : Original Article


1 Department of Industrial Engineering, Islamic Azad University, Zahedan, Iran.

2 Department of Economics, University of Sistan and Baluchestan, Zahedan, Iran.


The central goal of this research is to investigate the relationship between concentration ratio, skilled labour and efficiency in Iranian manufacturing industries. In order to measure the technical efficiency, we use the stochastic frontier analysis (SFA) method and data related to 131 of industries at 4-digit level of ISIC code during 1996-2009. To achieve the aim of study, we develop an analytical framework based on the fuzzy logic. Results suggest that there is a positive relationship between efficiency and skilled labour, while the concentration index has negative impact on industry's efficiency.


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