Journal of Economic Modeling Research

Oil Revenue Management (ORM) has always been one of the key challenges facing the oil rich developing countries. In this regard, the main objective of this paper is to provide a dynamic macroeconometric model adapted to the state of the Iranian economy. Also, the assessment of the dynamics of the National Development Fund (NDF) and its impact on macroeconomic variables are discussed. The results of the study, based on the out of sample and the four scenarios (the existence and absence of the NDF, the change in the share of the fund from oil revenues, the Fund's floating share of oil revenues, and the scenario of the fund exposure with temporary and permanent oil shocks) indicate that, The creation of a NDF in the short term will not improve the situation of macroeconomic variables, and the positive effects of such a policy will appear in the long run. The reason for this the private sector investment was time consuming and, consequently, the increase in non-oil sector production in the economy. Nevertheless, it is possible in the short term that by designing foreign exchange or budgetary policies, the initial downturn in the level of economic activity may be reduced by the stablization of the fund. Moreover, as in the mechanism of the fund, the floating share of oil revenues (adopting an anticyclical policy in allocating oil revenues to the fund) will help to reduce the negative consequences of shocks in the short run, because the lowest initial inflationary pressures, fluctuations in exchange rates and the net debt of the public sector occurs under this scenario.

Considering that the improvement of energy efficiency and the resulting rebound effect in the literature of energy economics is very important, hence the present paper uses the ARDL approach to estimate the direct rebound effect of the natural gas consumption in the residential sector in Iran. For this purpose, data from the period of 1986-2016 and the methodology based on the estimation of natural gas demand elasticity according to decomposed prices have been used. The results show that, firstly, the direct rebound effect of the natural gas consumption in the residential sector exists and, as a result, energy savings due to improved energy efficiency will be less than expected. Secondly, the direct rebound effect of natural gas demand in the short run is 69% and in the long run is 78%. Also, the findings indicate that there is no backfire effect of residential consumption of natural gas. Therefore, it is recommended to apply policies to improve the efficiency of natural gas consumption in Iran's domestic sector.

The business cycles are one of the most important economic indicators that they show the changes in economic activities during time. The study of business cycles is important because the understanding fluctuations in GDP and effective factors on these fluctuations help policy makers to plan better and more efficient. The main purpose of this paper is to investigate the effects of oil price shocks on business cycles dynamics in Iranian economy during period of 2005 to 2017 by using non-linear Markov switching model with the time varying transitional probabilities (MS-TVTP). So, first, the oil price shocks were extracted in four different modes, and then the effect of them on recession and boom regimes are investigated. The results of MS-TVTP model show that business cycles are affected by oil price fluctuations and shocks in Iran’s economy. The results indicate that, in all four modes which oil price shocks were calculated, the positive shocks in oil price increase the probability of staying in boom regime. Also positive oil price shocks increase the probability of transition from the recession regime in Iran’s economy. Also, with relative comparison of the coefficients of oil price shocks in the probability of staying in boom regime and transition from recession to boom regime, it can be argued that positive oil price shocks in recession period increases the probability of transition from recession more than the boom regime. In other words, oil price shocks in recession periods have a greater effect on rotation of economic situation and increase the probability of transition from recession regime, but in the boom regime, the positive oil price shock lead to increases the probability of staying in boom regime a little.

Homogeneity of groups in studies those use cross section and multi-level data is important. Most studies in economics especially panel data analysis need some kinds of homogeneity to ensure validity of results. This paper represents the methods known as clustering and homogenization of groups in cross section studies based on enviro-economics components. For this, a sample of 92 countries which produce the most greenhouse gases including CO2, clustered based on 18 criteria. Those criteria reduced to five primary components using factor analysis. Clustering of countries done by HCPC (Hierarchical Clustering on Principal Component) method. All 92 countries were clustered in 7 different groups. For each group properties of countries indicates the homogeneity of each cluster. In cross section analysis with many sections, especially analysis based on panel data, clustering, increases assurance of expected homogeneity and validity of result.

Given the importance of the issue and the undeniable role of the environment in the community's life, in this research, it is attempted to test the hypothesis of the relationship between the government size and composition of government expenditure (Current and developmental) on carbon dioxide emissions in Iran during 1971-2016 based on autoregressive distributed lag approach. To better explain, the above hypothesis is based on two parts of production (production industries) and Consumable (household, commercial, general; and transportation) has been investigated. Long-run results show that despite the fact that government size does not affect carbon dioxide emissions; the current cost ratio and developmental spending ratio of government respectively have a direct (undesirable) and reverse (favorable) effect on carbon dioxide emissions. In addition, the developmental spending ratio of government in both production and consumable sectors has a reverse effect on the carbon dioxide emissions of these sectors. However, the current cost ratio of government in both sectors does not have a significant effect. Energy intensity has a direct effect on carbon dioxide emissions in general format, and although the energy intensity of the production sector has no significant effect on the carbon dioxide emission ratio in this section but in the consumable sector, energy intensity is associated with direct (undesirable) effects on carbon dioxide emissions.

Oil price wild fluctuations impact the economies of developing countries as well as those of developed ones. Focusing on OPEC’s political risks as a proxy of precautionary demand, this study aims to disentangle oil price factors using an SVAR approach for 1994Q1 to 2016Q4. We disentangled oil price shocks into political risks, supplies, global demand for industrial goods and other oil price shocks. Our results highlight that shocks originated from different sources affect oil prices differently in terms of both their lifetime and directions. Besides, it is revealed that the structure of oil market has changed due to the 2008 financial crisis, increased oil price fluctuations, changes in OPEC’s behaviour and accordingly its market power, and the advent of new shale oil technologies, thus affecting oil price sensitivities. Therefore, we found out that OPEC’s political risks affected oil markets way more significantly in 2008-2016.

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.

The main objective of this study is modeling the dependency structure between the returns of oil markets, exchange rate and stocks of chemical products in Iran. For this purpose, the theory of Vine Copula functions is used to investigate the dependency structure. In addition to consider a linear relationship between financial markets in Iran, the nonlinear dependency structure of these markets is also estimated, and their dependence on their upper or lower tails is determined. The study period includes daily data (5 working days) from December 2008 to July 2017. Modeling of marginal distributions of GJR-GARCH models has been used. Then, using the Copula-GARCH approach, the structure of dependency between returns and the calculating of the Value at Risk (VaR) of crude oil, exchange rate and stock of the chemical product group returns have been investigated. Finally, the required back-test is performed on the basis of the loss function. The study findings show that both pairs of modeling returns are related to the same upper and lower tails. In addition, there is a same structural dependency on the distribution of the vine copula between the indexes of chemical products and the nominal exchange rate on the condition of the price of crude oil, which indicates the spillover between markets. Due to that spillover effect is the main source of financial risk, the structural dependence on the basis of vine copula functions makes accurate and reliable calculation of portfolio risk based on the VaR criterion.

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

Reducing or eliminating subsidies for the electricity sector in the economy is a good way to control the daily consumption of electricity and balance the cost of supply and demand players. By increasing or decreasing electricity subsidies, indirect taxes are reduced or increased. Under these conditions, assuming the stability of primary inputs and the stability of power generation technology and based on input-output modeling, the effects of rising electricity prices on the prices of manufactured goods in the 75 economic sectors were measured. The results of this simulation, which was performed under three models of electricity price increase of 7%, 16%, and 23%, show that the "communications", "manufacturing of food products" and "manufacturing of non-classified non-metallic mineral products" sectors are the highest. Taking into account the total benefits of increasing the price and its socio-economic costs for residential subscribers, the scenario of "increasing the tariff price of residential subscribers by 7%", "increasing the tariff price of public consumption by 16%", "increasing the tariff price of Water and Agriculture Production subscribers by 16%", "Increasing the tariff price of Industrial and Mining Production Subscribers by 23%" and finally "Increasing the tariff price of Other Uses Subscribers by 23%" can be a proposed tariff in increasing the price of electricity.

Based on theoretical foundations and empirical studies in the field of the relationship between natural resources and internal conflict, 4 states can be imagined: a. Positive relationship between natural resources abundance and internal conflict (hypothesis of political resources curse) b. positive relationship between natural resources scarcity and internal conflict (hypothesis of political resources endowment) c. Non-linear relationship between natural resources and internal conflict (combination of state A and B) d. Absence of relationship. Based on this, the main purpose of this article is to investigate the relationship between natural resources types and internal conflict risk in the MENAP region countries during the period of 2000-2019 using the System Generalized Method of Moments (SGMM). For this purpose, the index of the percentage share of total natural resource rent from GDP and eight separate indicators including: the percentage share of oil, natural gas, coal, forest and mining rent from GDP, the percentage share of fuel export and the export of ore and metals from the export of goods and the percentage share of arable land in the total area have been used. The results show that there is a U-shaped relationship between the total rent of natural resources and the internal conflict risk; In other words, countries with a shortage of natural resources as well as countries with an abundance of natural resources have a higher internal conflict risk than other countries. This U-shaped relationship is also confirmed for oil rent and fuel export. Also, coal and forest rent have a meaningless effect and arable land has an inverted U effect on the internal conflict risk in the studied countries. The evaluation of the marginal effect of the total rent of natural resources on the internal conflict risk shows that its value varies from -0.08 to 0.1. According to the other results, per capita income and democracy have a negative and significant effect, and population and religious and racial tensions have a positive and significant effect on the internal conflict risk.

The price of crude oil is one of the factors affecting economic indicators. Therefore, the prediction of oil prices and the accuracy of the applied methods have always been discussed by economists. In this study, the effect of all effective variables on the supply and demand of crude oil based on McAvoy's competitive theory is investigated, and the supply and demand are estimated using the system of simultaneous equations and conventional statistical methods. Then, using algebraic operations and the assumption of equality of oil supply and demand in the long term, the long-term potential of oil supply and demand is extracted with respect to each of the variables in the model. Based on the results, the world's gross domestic product (GDP) has the greatest impact on oil prices with a demand potential of 0.6039, and the world's military and security tensions have the least impact with a demand potential of –0.0110. After estimating the model, the prediction accuracy of three combined mothod is compared with conventional and single-variable methods of neural network and ARIMA. These three combined methods are: (a) neural network and system of simultaneous equations, (b) ARIMA and system of simultaneous equations, (c) neural network and ARIMA and system of simultaneous equations. The results showed that the combined method of ARIMA and simultaneous equation system provides better reslts for 5-year forecasts while the combined method of neural network and ARIMA and simultaneous equation system shows better results for 10-year forecasts.