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International trade expansion and export development have been the center of attention by the economists, policy makers and the cornerstone of planning in many countries of the world. Agricultural and industrial sectors are the crucial economic sectors in every country that have a parity role in preparing food for people and industrial inputs. This article using vector error correction models considers the simultaneous effect of economic policies on agricultural and industrial exports during the years 1971 to 2005. After testing the stationery, Johansen test was used for long run estimation. Results have shown that monetary policy has positive and significant effect on industrial and agricultural exports in short run, while interest rate and government expenditures have significant inverse and direct effect on industrial and agricultural exports respectively, and exchange rate policy has the same effect on industrial and agricultural export in long-run. Finally, the strength of each variable was investigated on export. It is recommended that increasing non oil export, the real value of interest rate is determined and by rising volume of money and then investing it and improving commodity supply, inflation will decrease and therefore non oil export will increase.

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On the factors affecting economic growth and per-capita income, the less attention has been paid to “population age structure”. We aim to investigate the effect of changes in population age structure on per capita income in Iran. To do this, we identify the most important effective channels according to review of literature. Then we design an empirical model that indicates the relationship between population age structure and per-capita income based on the neoclassical growth literature. In the next step we estimate and test the model in three specifications by Auto-Regressive Distributed Lags (ARDL) method during 1968-2010. The results indicate that the per capita income elasticity of labor supply (as the direct effectiveness channel of changes in population age structure on per capita income) is positive. In addition, indirect channels (which include savings, human capital and government spending) indicate that the per capita income elasticity with respect to an increase in share of population between the ages 15 to 64 is positive, and per capita income elasticity with respect to an increase in share of population below age 15 and above age 65 is negative.  

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This study investigates the time-varying correlations among oil and coin prices, and exchange rate in Iran. Since investment is a key factor in economic growth and development, so the necessary funds should be provided and directed towards manufacturing and industrial sectors. In addition, understanding the relationships among financial variables allows to the investor to reduce overall portfolio risk without harming to the return on investment. In this paper we use monthly data of the oil and coin prices, and exchange rate in Iran over the period 1991:3 to 2011:2 and examine time-varying correlations using Dynamic Conditional Correlation - Generalized Autoregressive Conditional Heteroskedasticity (DCC-GARCH) approach by G@RCH6 software. The analyses made in milieu of the world financial crisis (2008) show that the conditional correlations among assets are time-varying and world financial crisis causes significant changes in dynamic relationships among assets under study in Iran.

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Natural resources generate the major part of national wealth in resource-rich developing countries. Based on economic theories, if natural resource rents are reinvested continuously in other forms of capital, such countries can benefit from these resources. Thus, examining the mechanism of how to rents affect economic growth through capital accumulation channels is of great importance. Because of the importance of management of resource rents in achieving sustainable growth and development in resource-rich countries, this paper investigates the impacts of resource rents on accumulation of four kinds of capital (foreign, physical, human and social capital) in Iran during 1970-2014. To this end, a simultaneous equations system consisting of various capital forms is designed, and estimated by using Seemingly Unrelated Regression estimator. According to the findings, resource rents have positive effects on accumulation of foreign, human and social capital in Iran. But it is of negative effect on accumulation of physical capital. The results show that physical capital is affected by natural resource rents more than other kinds of capital. This is because of unproductive government investments in physical capital, hence not only resource rents increase physical capital but also they affect physical capital negatively.

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In this research, the impact of social capital through influencing the efficiency of government expenditure is investigated using three-stage least-squares model in Iran during 2005: Q1 to 2018: Q2. The effects of exchange rate, stock market index and oil revenues on non-performing loans of public and private sectors are also examined. Results suggest that given the increased efficiency of government expenditure, social capital has a significant negative impact on non-performing loans of public and private sectors. In addition, exchange rate has a significant negative impact on banking system’s receivables from public sector and a significant negative impact on banks’ receivables from private sector. Stock market index has no significant impact on non-performing loans of both public and private sector, since stock market is not liquid enough and has low share in financing businesses. Economic growth has also no significant impact on non-performing loans of both sectors, which can be explained by the impact of improvement in business environment and individuals’ purchasing power on their ability to repay their loans. Thus, by stabilizing economy (controlling the fluctuations of exchange-rate, stock market and so forth) and by improving social capital, it is expected that efficiency of government expenditure is increased and non-performing loans of both sectors is decreased.