Journal of Economic Modeling Research

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The investigation of determinants in Gross National Saving behavior especially effect of corruption, is one of the important issues in macroeconomics literature. For this purpose, we use the corruption perception index in dynamic panel data approach (Arellano and Bond Method). The Empirical results indicate that the corruption perception index (reduction of corruption) has positive and significant effect on the gross national saving. The main results of model estimation for two groups of oil and non-oil countries of MENA, shows that in oil countries the elasticity of gross national saving is more than of non-oil countries and reduction of corruption can be increase the national saving in oil countries. Moreover the results of model estimation shows that the inflation rate has negative effect and real per capita income and terms of trade variables have positive and significant effects on the gross national of saving in these countries.

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In recent years, regarding the export of Food & Beverage is important.in Iran and the economic researchers have been noted it. The main objective of this paper is to examine the impact of market concentration as a structural variable, advertising and R&D expenditures as behavioral variables and investment productivity on the Iranian food exports as a performance variable. For this purpose, the data for Iranian food firms has been extracted from the Statistical Center of Iran over the period of 2000-2007. Moreover, the empirical model of this study has been estimated by the Static Panel Data approach (SPD). The empirical results indicate that the market concentration, advertising and R&D intensity and investment productivity have positive and significant effects on the Iranian food exports and the impact of researching intensity (as measured by the ratio of research & development expenditures on sale) is more than other explanatory variables. Therefore, the market conduct is one of the main determinants of Iranian food exports. Also, due to the direct impact of R & D spending effect on exports, we can say that if managers and policy makers increasing the research and development activity in Iranian food industry sector can promote non-oil exports, especially exports of food products in Iran. Moreover, Facilitate and encourage producers to participate in exhibitions and international markets sales increased exports of goods and services can help.

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Environmental quality is affected by many factors such as economic and political inequality. The main purpose of this article is to investigate the effects of income and political inequality on the environment quality in the selected countries. Using the Generalized Method of Moments (GMM), the effects of gini coefficient, democracy index and income per capita, energy consumption and human development index on environmental quality are estimated for 57 countries during the period 2000 to 2012. The results show that income inequality and Political inequality significantly had a negative effect on environment quality. While the energy consumption has the negative effect on the quality of environment, improvement in human development index and the income per capita have a positive effect on the quality of environment. This finding might has important policy implication for policymakers and authorities to achieve sustainable development in different countries.