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The importance of productivity has made it to be one of the most serious discussions in industrial organizing. In economic literature, however, there are some arguments on the role of market structure in productivity changes. While some theorists point out that more competition leads to higher productivity, others believe that monopoly environment would be more efficient. This study examines the effect of competition- that is measured by the number of firms- on labor productivity in the Iranian industries. Using the panel data from the firms hiring 10 employees or more, the results suggest that monopoly and private ownership provide a more suitable environment for reaching higher productivity.

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The main purpose of this paper is to investigate the effect of market structure on innovation and R&D in Iran’s manufacturing sector. To do this, first, statistical data for Iran’s manufacturing sector has been gathered in International Standard Industrial Classification (ISIC) format, then mutual effects of concentration, innovation and R&D, advertising and profitability in different industrial activities have been analyzed using simultaneous equations system and Error Component Tow Stage Least Squares (EC2SLS) during 1996-2007. The results show that industrial concentration has a significant and inverted U-shaped relationship with innovation and R&D. In addition, R&D expenditure declines with increases in profitability. The investigation of the factors affecting manufacturing structure indicates that although innovation and R&D has no effect on manufacturing structure, but profitability and performance of top firms affect their concentration. Our findings exhibit the ineffectiveness of concentration and innovational behavior on industries performance; whereas increasing market concentration results in advertising expenses and innovational behavior of firms raises advertising expenses. Similarly, the lagged and accumulated effects of R&D confirm the existence of an inverted U-shaped relationship between concentration and R&D

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This study investigated the export status of stone fruits in Iran during 1997 to 2010. Export trends and revealed comparative advantage of indices, namely, Revealed Comparative Advantage (RCA), Revealed Symmetric Comparative Advantage (RSCA), and Relative Export Advantage (RXA) as well as Trade Mapping (TM) were investigated for cherries, plums, peaches, and apricots. Target markets for these products were ranked using numerical taxonomies. The results showed that Iran had export's comparative advantage for stone fruits only in 2007 and 2010. But, this index had a positive growth for the stone fruits in those years, indicating an increasing trend in the export status of these products. Trade mapping analysis indicates that although the export market for these products has declined during the period studied, Iran has taken a greater share of the market and is among the winner groups. The principal export markets in decreasing order were found to be Germany, The UK, France, Italy, the Netherlands, Russia, Saudi Arabia, Bahrain, Switzerland, the UAE, and Afghanistan.

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The purpose of this study was to investigate dairy processors market power in Iran. For this purpose, the dynamic imperfect competition model, in which processors are allowed to exert market power in both downstream (selling dairy products) and upstream (buying raw milk from dairy farmers) was applied. Market power parameters, dairy products demand, and raw milk supply elasticities were jointly estimated in a system of equations including market margin, dairy demand, and raw milk supply equations by none linear estimation technique. Data for the period 1992 to 2012 on the industry level were used for estimating an empirical version of the model. The result indicated that conjectural elasticities values were a departure from zero, which reflected non-competitive behavior in dairy market and in raw milk market specifically. Among three dairy products including pasteurized milk, yogurt, and cheese, the conjectural elasticity was the highest for the pasteurized market and the lowest for yogurt. The result suggests that dairy industries processors exercise marketing power in the downstream and upstream market in the dairy products supply chain. Therefore, policymakers must make appropriate policy for facilitating entrance conditions for new dairy processors and improve farmers’ marketing cooperative so as to have more competitive raw milk price.