Investigating The Impact of Oil Revenues on Income Distribution in OPEC and Non-OPEC Member Countries, Using the GMM Method

The increase in oil prices increases the foreign exchange reserves of oil exporting countries and these revenues increase the power of the domestic economy. Improper planning and improper use of these income sources can lead to an increase in income inequality in these countries. Income distribution is of particular importance as a performance variable that affects other economic variables. Using the econometric method based on the generalized moments method (GMM), this research examines the relationship between oil revenues and income inequality in selected oil countries. GDP, inflation, government size and labor productivity, independent variables and income distribution are considered as dependent variables of the model. The results show that oil revenues, GDP, inflation and government size have a positive and significant effect on the Gini coefficient. Also, labor productivity has a negative and significant effect on the Gini coefficient.The practical and political results of the research emphasize that because the increase in oil revenues in oil-exporting countries leads to an increase in inequality, therefore, budget planning should seek to reform the government's spending mechanism, because the main reasons for the relationship between income and income distribution in the way of spending planning and government expenses are hidden.