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     The main goal in this research is to survey and determine the actual structure of the demand function through the BOX-COX consumer goods demand system which includes various forms of demand functions. Using nested and non-nested methods the estimation of consumer demand function is done. Nonlinear seemingly unrelated regressions are also used for the periods of 1982- 2007 via the combined statistics of income groups in urban areas in order to calculate  uncompensated price elasticity and expenditure elasticity associated with the demand function estimate. Results of nested and non-nested tests show that the BCDS and AIDS models are near performance. The elasticity figures resulted from the BCDS and AIDS models have also revealed that food group is an essential one, social affairs (clothing, health, leisure and education) are regarded as almost luxury, and miscellaneous group (transportation and others) is quite luxury. But the group of housing (housing and furniture), in the BCDS model is almost luxury and in the AIDS model considered as essential. The elasticity of demand was confirmed by the demand law and cross elasticity of demand has also shown that the food group compared with the social affairs is considered as supplementary and to the group of housing and miscellaneous is regarded as a substitute. The social affairs group compared with the miscellaneous group is supplementary and to the housing group is a substitute and finally the miscellaneous group is considered as a substitute to the housing group.  

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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 purpose of this study is to examine the household’s behavior in response to the kinds of the wealth and the estimation of marginal propensity to consume out of wealth. By using Ando-Modigliani consumption model and applying Engle-Granger co-integration strategy, marginal propensity to consume out of wealth is estimated in Iran during 1982-2008. The various forms of wealth as durable good, housing, bonds, savings, combinative and normal good are considered. Results show that households respond to kinds of wealth differently. This study finds that the marginal propensities to consume (MPCs) out of labor income and wealth, in the form of durable good, are 0.93 and 0.012, respectively. In addition, the MPCs out of labor income and wealth in the form of housing are 0.8 and 0.027, respectively. Regarding bonds as wealth, the corresponding MPCs are 0.67 and 0.055, respectively. For savings, the corresponding MPCs are 0.58 and 0.081, respectively. In combinative form of wealth, the computed MPCs are 0.7 and 0.04, respectively. Finally, considering normal goods as wealth, this study reaches the MPCs of orders 0.59 and 0.16, respectively. The long-run relationship shows that individuals’ MPC is about 0.79 apart from what types of wealth they hold. One important finding is liquidity allocation by individuals facing various kinds of wealth. This study indicates the fastest velocity of liquidation of savings and the lowest velocity of liquidation of durable goods.