JOURNAL OF SUSTAINABLE GROWTH AND DEVELOPMENT (THE ECONOMIC RESEARCH)
Year:2013 | Volume:12 | Issue:4|Papers Count:9

Ramsey model is one of the most important basic models to study intertemporal resource allocation. This model is derived from microeconomic optimal principle so it has a key role in macroeconomics with micro foundations. Hence, in many economic researches it is considered as a reference theory. Application of this model in economy of Iran will provide an appropriate theorem framework for explaining empirical facts of the Iranian economy and will introduce a new approach to researchers. The main idea of this study is generalizing Ramsey model through including terms of trade and its calibration in the economy of Iran. For this purpose first, the model is explained. Then, the first order condition is derived and mathematical optimal path of variables is solved. Finally, the model is calibrated by GAMS package for economy of Iran in time period (2006-2036). The results indicate that there is a feasible solution for model and the optimal path of variables can be observed. The optimal path of Gross National Production and Consumption are increasing but the optimal path of capital stock and investment is primarily increasing then decreasing. In the final section of this paper a sensitivity analysis is presented. Some scenarios are designed for the important parameters of model like time preferences rate, intertemporal substitution elasticity of consumption, labour growth rate and output elasticity of capital. Sensitivity analysis shows that output elasticity of capital and labour growth rate increased the social welfare and shifted optimal path of variables upward. But time preferences rate and intertemporal substitution elasticity of consumption had inverse effect on social welfare and optimal path of variables.

Shadow economy is an important part of economy in almost all countries especially the developing ones. Most of active firms in this part of economy have negative externality on the environment. Considering the importance of sustainable development and growing international pressures to maintain and support the environment more and more attentions have been drawn to the factors affecting and threatening environmental health. The present paper for the first time considers the role of variables like polity index and active population to total population ratio and how they affect the shadow economy. In addition to the main direct effects of these variables on shadow economy the indirect effects of causal variables through interaction with shadow economy are also examined. Since the relationship between shadow economy and air pollution has been somehow disregarded in economic literature to a large extent in Iran and to some extent at international level the present paper for the first time focuses on the relationship between shadow economy and air pollution. The results indicate that on average the ratio of shadow economy to GDP is 12.25% and a 1% increase in the size of the shadow economy raises the water pollution by 0.17%.

In this paper the impacts of oil price fluctuations on the household welfare for different income groups have been studied using computational general equilibrium model. Equivalent Variation (EV) criterion is also used to evaluate changes in household welfare. The results show that oil price fluctuation has a greater impact on income, expenditure and welfare of urban households compared with the rural ones. In other words, dependence of urban household income on oil price is stronger in comparison to the rural ones. It has also been revealed that an oil price increase is more effective than the price reduction on household welfare, income and expenditure. Ratio of EV to total expenditure is almost the same for the poor and rich households, implying that both of them suffer a percentage of welfare loss in the same way.

For determining the profit in transactional contracts, there is no a comprehensive theory. Some viewpoints are very general and others are based on exchange rate of return, which contain speculative difficulties. Some others use international Libor rate and so on. Due to the lack of a consistent theory, this paper is introducing shadow cost approach to fill the gap in question. This is indeed going to estimate capital return or opportunity cost of capital. Introducing an efficient method is the main finding of this paper. In terms of methodology, this paper is based on statistical analysis and econometric methods.

Science and technology can have a major role in growth and creating value added of communities. Research and development are important economic issue that cause technological changes and therefore have a significant role in development of technology and increasing production capacities. Although recently developing countries have realized the importance of R&D, their production units are unable to invest more in R&D section. It is also believed that in the early stages of development, the existing technological gap between these countries and technology leaders decrease the success possibility of R&D efforts and as a result, these communities don’t have reasonable technological basis for innovation. So in the early stages of development, in addition to R&D efforts, import of capital goods can also be effective in developing technology and increasing production capacities of developing countries. In this study, the effect of internal R&D capital stock and external capital stock on value added of the Iranian medium and large industries is investigated over the period of 1994-2007 by applying panel data approach. The results indicate that internal and external capital stock, human capital and internal R&D capital stock have a significant and positive effect on added value of the Iranian medium and large industries during the mentioned period. The research findings have also revealed that although the number of labor force has a positive impact on added value of these industries, it is not statistically significant.

Although many firms enter into the market in completely different sizes, recent facts show that the size distribution of new-entrant firms tend to more homogeneity than disparity over time. This is known as industrial dynamics in the literature of industrial economics. The dominant view in this area is learning by doing, in which firms can enter into an activity at any sizes. However, they will learn over time that which size of the market is effective enough to enable them to remain in the market in the long run to give them the chance to adjust their size. Meanwhile, firms that failed to learn it in a reasonable time will have to exit the market. Therefore, the most significant objective of this paper is to review the way of size distribution in firms in arrival time and its adjustment over time in Iran that is not so far taken into consideration well. This subject can have prestigious application for new-entrant firms as well as increasing their lifetime in the market by decreasing adjustment time for incumbent firms. A descriptive-analytical method has been applied for doing this research. The industrial firm data collected by Statistical Center of Iran (SCI) in ten consecutive years are also used for this purpose. The results indicate that the average size of new-entrant firms is smaller than that of incumbent ones. In other words, manufacturing firms in Iran are born smaller in size in comparison with incumbent firms. Additionally, broad size dispersion of the firms at arrival decline during the learning by doing in most industries and tend to more homogenous size distribution. The results have also revealed that although in most selected industries the average size of new entrants has been increased, the intensity of increase is separable in three groups: 1. firms smaller than industry average, 2. firms with close size to the average industry size and 3. firms larger than industry average. Average growth of firm size located in the middle range (group 2) is about half of this measure toward group 1. However, average growth of firm size located in larger groups (group 3) is about half of this measure toward the group 2. This subject as the most essential findings of the industrial dynamics in the economy of Iran indicate that -unlike the usual- small and medium criterion could be modified to suit the type of industry or be influenced by time. Finally, the findings of this research imply that applying absolute definition for a variable conception (small, medium and large firms) cannot be considered rational.

The purpose of this study is to find the key Iranian sectors in terms of output and employment. This research is done based on the Input-Output table of the year 2001 and Extraction Method. In this regard the economic activities are aggregated into 36 sectors. The results show that Forward and Backward output linkages were significant in five sectors namely agriculture, construction, wholesale and retail services, transport and other services. Forward linkages were strong in six sectors including oil and natural gas, mines and chemicals and petrochemicals, nonmetallic minerals, basic metals, water, gas and electricity as a group. On the other hand, backward linkages were very strong in four sectors such as food industries, transport equipment and machinery, education and health services and public services. Estimating the direct and indirect employment generation shows that agriculture, construction, wholesale and retail services, food industry, transport, education and health services and transport equipment are the main employment generating sectors. Spearman Rank Correlation Coefficient is also used to find out if there is any correlation between high ranking activities in output and employment. The results also indicate that there is a high rank correlation between backward output linkages and employment generation but week forward output linkages and employment generations. This shows that those activities which serve other activities in domestic market through its backward linkages are more important in output and employment generation. The weak rank correlation between output and employment generation indicate that these activities are highly depending on domestic demand but do not have much linkage with other sectors in the domestic economy, perhaps due to their dependence on imports for their inputs. Total average rank correlation between key sectors in output and employment generation shows a very weak correlation between the two, indicating that the sectors generating high linkages in output are also the same activities creating linkage in employment. The research findings reveal that how an oil producing country, using its oil revenues for imports and leading the expansion of wholesale and retail activities, transport services and public services in education health and other bureaucratic administration services, undermines the development of its manufacturing industries which are labeled as “engine of development”.

This paper examines the existence of b-Convergence between per-capita incomes of selected Islamic countries. For this purpose, data over the period 1965-2006 and a time series approach proposed by Vogelsang (1998) are applied. Robustness of the estimated parameters to the presence of unit roots and/or serial correlations in the residuals is the main advantage of this method. The results show that per-capita income of most countries is converging to the average per-capita income of the selected Islamic countries, which provide evidence of b-Convergence. Cameroon, Indonesia, Malaysia, Niger, Chad, and Togo are the countries that have shown some forms of divergence either before the break date or after that. The estimated break dates are clustered and mostly related to the energy shocks in 1974, 1979, and 1986.