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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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The main objective of this paper is to evaluate the effect of R&D on profitability of high -tech industries with new evidence from the Iranian industries carrying four- digit codes. The Structure- Conduct- Performance (SCP) paradigm, which is relatively well known in industrial economics and in organization management, provides the theoretical construct that guides our empirical model formulation and execution.  The data is compiled from observations made at the plant level covering all industrial plants employing ten or more persons and carrying four- digit codes within the time span of 1994-2007. The model used essentially consists of a simultaneous equation system framework grounded into a panel data approach and estimated by Two-Stage Least Squares (2SLS). Our findings indicate a positive and significant effect of R&D expenditures, measured in intensive form, on profitability of high-tech industries as evidenced by the Iranian case. Our more notable finding is the positive effect of lagged profits on R&D expenditure intensity, revealing a likely mutually enforcing relationship between profitability and R&D intensity in high tech industries