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


Volume 3, Issue 1, Number 4, Pages 66-82, Published Online January 20, 2015

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Laleh Arbabi and Dr. Mohammad Nabi Shaihaki Tash


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.


concentration index, skilled labor, technical efficiency, fuzzy logic.


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1 Comment

  1. India says:

    Alihrgt alright alright that’s exactly what I needed!

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