Journal of Economic Modeling Research

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  The aim of this study is to review the causal relations between TFP growth and inflation as one of the attracting issues in Macroeconomic literature. For the first time in Iran, we have used the wavelet decomposition technique to study this relation. Both TFP growth and inflation series between 1960-2006 are decomposed up to three levels. Our analysis of causality relations between all the composed and decomposed series shows that though no statically meaningful effect between original series has been proved, there are some negative relations between decomposed series in first and second level. Moreover, our study reveals some previously unknown spillover effects between various frequencies of both series as explained in paper. Finally, on the basis of relations founded between decomposed series of inflation in different frequencies, we introduce a new instrument to measure the volatility of inflation.

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  The intensive effects of “targeted subsidies plan” and its implementation and that of the price of energy carriers on macroeconomic variables such as private consumption and Gross National Product, therefore increase in the price of energy carriers and the relevant issues have been debating and discussing for a long time. Regarding the significance of the issue and also its effect on the economic and society welfare, further and more comprehensive investigations into this subject seems to be necessary. This paper is presented with a review of previous studies and then explores the effect of the increase in the price of energy carriers on the three important macroeconomic variables, i.e. GDP growth, inflation and private consumption in the context of a structural vector regression to model SVAR. The results show that due to implementation of this plan, the economic growth and the private consumption decrease but the inflation will increase. The results showed that, the energy price index shocks the most influence on inflation variation are explained so that voters, in the medium term and long-term changes and about 40 percent of fluctuations in inflation, energy price shocks is described. Other findings of this study is that, in the long-term energy price shocks indices respectively about 20 and 11 percent of the fluctuations in private consumption and gross domestic product by the explained. It should be noted that all results, without considering the effects of resource redistribution payment received from government subsidies are.

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Industrial energy demand analysis has always been one of the leading fields of research in economics. This issue is more critical in the case of developing countries especially those with transition experiences. In this paper, third generation of dynamic factor demand models for the Iranian manufacturing industries is estimated to analyze the speed of adjustment in factor demands. Data which is used in this study is an Iranian industrial plant based on two-digit international classification code during 1374-1386. The translog functional form is used as model specification. The main findings are the complementary relation between energy carriers, electricity, and capital and low adjustment speed of capital stock. In Iranian manufacturing industries, demand for energy carriers and capital, with expansion of manufacturing activities and technological change has increased, while the demand for labor has decreased.

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This study examines the social cost of banking industry in Iran (17 governmental and private banks) in an unbalanced panel data model. To conduct estimations, two different approaches were taken: 1- Welfare Triangle approach 2- Libenstein’s approach. In the former, welfare triangle is measured assuming banking industry operating in full technical efficiency however, the latter includes both the effect of welfare triangle and the cost of likely technical X-inefficiency. The result of the first method showed that the social cost of banks in Iran is little, amounting to be less than 1 percent of GDP in 2008 while within the same period, the second method resulted in 4 percent of GDP, as the social cost of banks in Iran.

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The foreign direct investment is one of the economic variables that can positively affect the economic growth, but according to some researches this does not apply to some countries. These researches implicate that this lack of positive effect is due to domestic qualification of the home country. One of the essential qualifications for positive effectiveness of foreign direct investment on the economic growth is the existence of developed financial market. Therefore, in this research we intend to examine the role of financial market in the effectiveness of foreign direct investment on the economic growth. To do this we made use of the data from 57 countries in the period 1990-2005 and the econometric technique of panel data. The results show that in developed countries because of their financial market, the effect of foreign direct investment on economic growth is positive and significant whereas in developing countries this effect is not significant.

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The Poverty measurement and its determinants are the most important factors in poverty alleviation programs. In this paper, we estimate poverty line and its dimensions by using Linear Expenditure System. To that end, we use household level data from the Statistics Center of Iran during the period of 1994-2008. We examine the main determinants of poverty for urban households using a probit model. In this model, we assess the impact of key household characteristics on poverty. The results show that the poverty likelihood decreases if the educational level of the head of the household increases. In addition, the chance of being poor declines in a household headed by a male. The age of the head of the household, the ratio of income earners in the household, and the household size are other factors that have a significant role in the probability of being poor.

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This paper focuses on the role of uncertainty about the number of surviving children. The survey discusses the effects of declining mortality rates on fertility, education and economic growth. The construction of the paper is an OLG model in which individuals make choices about fertility decision over their lifetimes subject to uncertainty about the immortality. The simulation of model using actual changes reveals the fact that if the uncertainty about child survival enters to growth model, the population becomes an inverted u-shaped function of income per capita. As the mortality rate and thus uncertainty falls, the precautionary demand for children decreases. Furthermore, lower mortality encourages investment in children’s education .Also the calibrated version of the model using realistic estimates demonstrates that at low levels of income, population growth rises leading to Malthusian steady-state equilibrium, whereas at high levels of income population growth declines leading to a sustained growth steady-state equilibrium.

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The Phillips curve usually has been estimated in a linear framework which implies a stable constant relationship between inflation and unemployment. Some of the studies claim that the slope of the Phillips curve is a function of macroeconomic conditions and also the relationship is asymmetric. This article deals with a smooth transition regression model for relationship between inflation and unemployment for Iran, during the period of 1971 -2007. Smooth transition regression model is a non linear time series regression model which could be considered as developed form of regime switching regression model. Results show that there is a negative and nonlinear relationship between inflation and unemployment in short-term. Regarding this result it's highly important for policy makers to be able to make a relationship between these two variables

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Intermediate goods are another produced factor of production, like capital. Considering intermediate goods in production function makes multiplier be even larger than the one. In this paper, based on the approach of Jones (2007,2010) We computed multipliers by intermediate goods. For this purpose, we used Input – Output table of Statistical Center of Iran (base year: 2001). Finding show that 10.6% of total products used in inter- sector transaction and 4.28% used in intera-sector transaction. Therefore, the domestic multiplier is 1.383 and import multiplier is 2.117 and total multiplier is 2.929.These results indicate increase in the multiplier. The industrial sector and mining sector produce the most and the lowest share of domestic intermediate goods, respectively. The highest and lowest shares of imported intermediate goods between economic sectors are in industrial sector and water sector, respectively

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This study investigates the effects of terms of trade shocks and international reserves on the real effective exchange rate. For this purpose is used panel data technique and data related to 20 countries for 1980- 2008 period. Estimation results show that international reserves have buffer effect in terms of trade shocks and cause terms of trade shocks have less effect on real exchange rate. Of course this result confirms in developing countries, but don’t confirm in developed countries. In addition according to results, reserve effect in reduction terms of trade shocks effect in oil exporting countries is more than other countries. Also, according to estimations in this study, increase in financial development reduces buffer role of international reserves.

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This study tries to examine the way housing residential investment in Iran's urban area is influenced by the shocks of oil revenues, and for that, time series data spanning the period 1991:1-2007:4 are deployed in a Dynamic Stochastic General Equilibrium (DSGE) model including households, firms producing new residential houses, and the production of other economic firms as well as oil sector. The model is based on some simplify assumptions suitable to Iran's economy characteristics as: Iran as a small economy regarding capital flows, Oil Exports and goods imports and no price stickiness in housing sector. Moreover, the allocation of resources in the economy is determined by a central planning. The Model's solution and simulation is processed through using DYNARE as a subset of MATLAB software package. The results showed that the incidence of extreme volatility in the short ‌ behavior of housing residential investment in Iran's urban area, due to shocks of oil revenues, shocks was not Persistent and quickly disappeared. This implies that Iran's economy is suffering from Dutch Disease.

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Convergence hypothesis includes two types of beta and sigma. In this study, we examine convergence hypothesis among Iran’s provinces and discuss the effect of internal net migration in that context since 2000 to 2007. The results indicate that poor provinces grow faster than rich ones and there is beta convergence in Iran. About sigma convergence, we found that the dispersion of GDP per capita increase among these provinces over the years. Immigration is one of the factors that could influence economic growth of provinces and convergence among them. The results show a direct relationship between net immigration and per capita GDP growth of provinces. When the variable of net migration is included into convergence equation, it increases beta coefficient. So, net migration has a negative effect on convergence. Immigration flows more from the poor provinces to rich provinces and increases the gap among them.

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    The number of factors affecting total factor productivity has been increasing far from those which considered in growth models. So, institutional factors have been attracting strong attention of researchers. This paper aims at investigating the effects of these institutional factors together with traditional factors on TFP growth during 1971-2007.

  For this purpose, we present a State-Space model. Using this approach, TFP has been regarded as a latent variable and in the state equation, we introduced some exogenous variables. Some endogenous variables which were mainly measures of institutional factors have been specified as proxies. Our result show that the introduced measures of institutions such as governance(political stability and accountability) institutions and degree of government intervention together with an older and known institutional factors, such as macroeconomic instability, have significant effects on TFP growth. In addition, the residuals from state-space model (either deterministic or stochastic) were different from the residuals of other models.

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    This study aims at determining the optimal environmental tax policy in the context of a dynamic model. For this purpose, clean technology diffusion was added to the AK growth model and the theoretical model has been generalized to the open economy. The main feature of the economy is creating pollution in the process of economic growth and its negative impact on social welfare. The diffusion of clean technology reduces pollution emission and has a positive effect on environmental quality and social welfare.

  The Hamiltonian solution of the model indicates that the steady state growth rate and optimal tax pollution is affected by the consumer preference toward consumption and environmental quality, pollution elasticity with respect to production, clean technology diffusion, foreign growth rate, inverse elasticity of intertemporal substitution , depreciation rate of capital and trade parameters.

  The results show that the optimal tax rate in Iranian economy is about 15 percent. Furthermore, sensitivity analysis shows that the emission elasticity of pollution subject to the production and environmental preference parameters have larger impacts on optimal tax rate than foreign growth rate and trade parameters.

 

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  Oil revenues play a significant role in the government budget in Iran and have also an important impact on GDP. This study aims at providing a practical solution for the question of how oil revenues should be managed. In this regard, a Computable General Equilibrium (CGE) model has developed to examine the direct effect of distribution of oil revenues on GDP in both static and dynamic approaches .

  The results of static model show that the direct distribution of oil revenues to households has a negative effect on the government expenditures and therefore decrease the GDP . The dynamic model allows the conversion of savings into investment and capital formation. So the results of running this model show the positive effect of direct distribution of oil revenues on GDP and also the negative effect of this policy on the government current spending. Therefore, the results confirm that direct distribution of oil revenues is an effective policy in reducing the dependence of government on oil revenues and also in relying more on people and the tax revenues .

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The magnitude of economic growth depends on the growth and investment in key economic sectors. Thus, one important goal of policy makers and economic planners in any society is to identify key economic sectors. This paper aims at identifying these sectors in Iranian economy using stochastic input-output analysis. Stochastic analysis is used to investigate how the inherent imprecision affects the concomitant key sector analysis in case of utilizing aggregated data. The analysis is based on Iranian input-output table for the year 2001, using distance estimation and Monte Carlo simulation. Results of the non-stochastic approach indicate that among 25 economic sectors in aggregated input-output table, six sector-groups are the key sectors while, in non-aggregated input-output table with 99 sectors, 13 sector-groups can be identified as key sectors. Finally the suggestion is that to identify key economic sectors the non-aggregated input-output table should be used.

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The concept of “Innovation” has changed considerably in recent years. According to new theories, the innovation emerges in a system of interrelated elements and determinants during which the idea changes to a commercialized output or process. The literature on the innovation has concentrated mainly on various aspects of innovation chain separately. In this paper we tried to investigate the general effects of the whole elements of the innovation chain simultaneously. These elements are: R&D expenditures, physical capital formation, human capital and patent filling (residence and non-residence). We utilized multivariable time-series methods including cointegration and vector error correction model (VECM) to assess the long-run effects of innovation elements on total factor productivity in Iran. Results show that excluding the human capital variable, other elements of innovation chain have positive effects on TFP among them, residence and non-residence patent filling having the normalized long-run coefficients of 0.58 and 0.48 respectively, are the most important factors affecting TFP in Iran.

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Unobservable productivity shocks cause selection and simultaneity problems in firm’s decisions and these problems cause estimators such as ordinary least squares, have biased estimation for coefficients of production function inputs. In this study, data of five automaker companies in the period of 1383-1387 have been used and production function of car industry have been estimated by ordinary least squares, fixed effects, random effects, Olly and Pakes (1996) and Levinsohn and Petrin (2003a) approaches. The results show that fixed effects and Levinsohn and Petrin (2003a) approaches can’t be appropriate for the production function estimation of car industry. In other words, reaction of automaker companies to productivity shocks will not be done through adjustment in labor, capital and energy demands and there is no significant correlation between inputs adjustment and productivity shocks in car industry. But estimated coefficients of energy and capital in semiparametric, random effects and ordinary least squares approaches show that estimated coefficients of energy and capital in random effects and ordinary least squares approaches are upwardly and downwardly biased, respectively. These results are perfectly consistent with the viewpoint of Olly and Pakes (1996) about bias of traditional estimators and show that automaker companies, in response to the productivity shock, adjust their investment level. In addition based on estimation of semiparametric approach, output elasticity of capital and energy will be respectively 0.82 and 0.64.

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Transportation has been one of the human primary needs and it has been found a wider range with the economic and social development, today it’s considered as a symbol of civilization. It is one of the infrastructure sections in every society that, it not only influences on the development process but also will be changed during development. So, this study investigated the effect of transportation infrastructure on economic growth in some of Iran's provinces by using of panel data model and data from 2000 to 2011. The results indicate that transportation infrastructure as a variable had a positive effect on economic growth. Moreover, provinces that had more populations could help the promotion of the economic growth by changing the underlying structures such as the transportation capacity and the quality of the transportation systems.

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The main objective of this study is to investigate the effects of oil shocks on GDP, prices level, money and exchange rates in Iran by using the structural vector error correction (SVEC) approach model covering the period 1980Q2-2010Q1. The findings of this study reveal that positive shock in oil real price has significant and positive effect on the real GDP in the short, medium and long. The impact of oil price shocks on domestic prices in the short, medium and long term is negative and significant, such as creating a positive shock to the real price of crude oil, reduce the domestic price. In addition, a positive shock to the real price of crude oil has the negative effect of the exchange rate in the short, medium and long term. However, the impact of oil price shock on the real exchange rate is permanent. Imports also will increase, due to the increase in wealth and demand for intermediate products. On the other hand, a positive shock to the real residual money in the short run cause to immediate increases in real out put.