Journal of Economic Modeling Research

This study examines the relationship between per capita income and per capita dioxide emissions in the form of a new definition of the Environmental Kuznets Curve, to investigate how corruption influences the income level at the turning point of the relationship between per capita dioxide emissions and income, in developed and developing countries the period 1994-2013 through the use of a panel data model. Our results support the Environmental Kuznets Curve hypothesis for developed countries and existence of an U-shaped relation for developing countries. We find evidence that the higher the country's degree of corruption, the higher the per capita income at the turning point for developed countries and the lower the per capita income at the turning point for developing countries than when corruption is not accounted for. Also, the share of renewable energy in both groups of countries has a negative and significant effect on per capita dioxide emissions, but the positive effect of urbanization rate in developed countries is significant and in developing countries is not.

In recent years, some research has focused on the importance of the origin of an oil shock for macroeconomic dynamics in both oil-exporting and importing countries. The existing literature lacks a proper open Stochastic Dynamic General Equilibrium (DSGE) framework to investigate the effect of the origins of oil shocks on macro variables in a two-country model consisting of an oil-exporting county and an oil-importing country. To this end, we develop and solve a new Keynesian DSGE model to show how the different oil shocks originating from oil supply or oil demand, might have diverse impacts on key macroeconomic variables in oil-exporting and importing counties. For the case study, we use data from Iran as an example of an oil-exporting country that trades with the rest of the world. Our DSGE model is estimated by using the Bayesian method for the period 1986:1-2017:4. The result shows that an oil shock originated from the shortage of oil supply (an exogenous decrease in Iran's oil production) decreases total production, non-oil trade, employment, inflation and consumption in this oil-exporting country. While a negative oil supply shock increases production costs and reduces production and consumption in Iran. However, an oil shock originated from an increase in the demand for oil raises output, non-oil trade, employment, consumption, and inflation in Iran as an oil-exporting country while a demand-side oil shock boosts production and increases inflation in this country.

This study examines the Kuznets environmental curve among D8 countries in the period 1961–2016. The Kuznets environmental curve shows the reversed U-shaped relationship between economic growth and environmental degradation. In this paper, two methods of time series estimation and smooth panel transition estimation were used to test the hypothesis of this relationship. Also, the ecological footprint index was used as an indicator of environmental degradation. The time series estimation results show that there is a nonlinear relationship in all D8 countries but the classical Kuznets hypothesis was confirmed only in Malaysia, Egypt and Turkey and in other countries the relationship was not inverted U. In Iran, the relationship between GDP per capita and the per capita ecological footprint is N-shaped, and at the GDP levels of $5864 and $10514, the relationship between the two variables will change. On the other hand, testing of the Kuznets hypothesis by using panel smooth transition models showed that there was a nonlinear relationship between GDP and ecological footprint in D8 countries with a threshold. There was a direct relationship between ecological footprint and GDP per capita when economic growth below 8.3 percent and reverse relationship when economic growth above 8.3 percent