فهرست مطالب ناصر خیابانی

In the labor market literature, Shimer's criticism of the standard search and matching models indicates a low elasticity of the labor market as to the technology shock. As a result, the standard search and matching model is not able to explain the fluctuations observed in the main variables of the labor market, such as unemployment and job vacancies. In other words, in the standard model of search and matching with Nash bargaining, the fraction of fundamental surplus is large. Various explanations have been proposed to increase the elasticity of labor market compression to changes in productivity, and they all entail reducing the fundamental surplus fraction. By integrating the current and expected monetary policy induced debt overhang friction in the production and financial intermediatory sectors with a standard search and matching model this study aims at analyzing and pursuing how inclusion of this friction, through reducing the fundamental surplus and raising elasticity of labor market compression, could explain the excessive volatility in unemployment and job vacancy opportunities and thereby rendering a new solution for the Shimer’s puzzle. Further, the basic idea of this research was developed within a dynamic stochastic general equilibrium model including the key components of the search and matching model entailing the fundamental surplus fraction.  The resulting integrated model can be viewed as a theoretical framework for investigating the implications of including long-term risky nominal debt and the debt overhang for the fundamental surplus fraction in the structure involving financial frictions and the main features of the search and matching model subject to firm-specific productivity shocks and inflation. Considering the Iranian economy features, the model has been simutated for two cases one involves inertia in prices and the other one entails flexible prices.  The findings show that a monetary regime that leads to inflation would ensue the debt overhang episodes via reducing the real value of companies' debts. As leverage and default rates upsurge, firms pass up new investments and this leads to reduced labor force recruitment, job vacancy opportunities cut, and increased unemployment. As such, the debt overhang in companies lowers the fundamental surplus fraction and thus aggravates the impact of shocks on the elasticity of the labor market compression.

To understand the behavior of housing prices in the country it is necessary to investigate the spatial interactions of interconnected regional markets. The discussion on housing prices highlights the potential spatial heterogeneity and cross-sectional dependence in different regions. It is important to pay attention to the source of cross-sectional dependencies to better understand the dynamics of housing prices in different regions. Cross-sectional dependence can be caused either by the role of space in economic processes or by common shocks that affect the entire economy, such as the oil shock. Using a spatio-temporal housing price diffusion model, the study found that the Tehran region, as the center of economic development and oil revenues, was a dominant region, and that shocks to Tehran were propagated contemporaneously and spatially to other regions. The results show that in modeling the spatial diffusion of housing prices, financial proximity is more important than geographic proximity, and regions with stronger financial links with Tehran will be most affected by shocks to this region in the long run.

An inefficient firm causes a waste of resources by using a non-optimal combination of capital and labor and especially energy. Measuring inefficiency and identifying the factors that cause it is vital in achieving the firm's potential production and, as a result, the sustainability of economic growth and increasing the economic well-being of the society. Meanwhile, choosing the right model to measure inefficiency is always one of the basic challenges among researchers in this field. This study attempts to provide an overview of the concept of efficiency and its types and different measurement models with an emphasis on the Frontier Analysis. Considering the large volume of theoretical and experimental studies in inefficiency, our review aims to provide a proper understanding of their strengths and weaknesses by investigating the evolution of the models demonstrated in the literature, and thus helps the researcher to create a clear framework for analysis and choosing the appropriate model. Furthermore, this study offers suggestions to measure inefficiency as accurately as possible from the theoretical and technical viewpoints, which have been understudied in the literature.

This paper examines the dependence structure between two currencies (Yuan and Euro) before and after Yuan joins the SDR basket. To this end, we propose SJC copula Time-varying approach for the daily closing price of these currencies for the period 2005-2020. According to the evidence, the behavior of Chinese monetary authorities in response to Euro - Dollar has changed. In the first period, exchange rates are more correlated when they are depreciating against dollar compared to when they are appreciating. This means that the Chinese monetary authorities' priority has been to maintain a competitive advantage in world trade and thus to intervene to depreciate yuan as euro depreciates against dollar. In the second period, with the internationalization of yuan, China's strategy changed and reacted more drastically to the appreciation of Euro against dollar; PBOC intervenes to appreciate Yuan, stabilizing its currency price. In this case, by supporting investors, it encourages them to maintain and even increase the Yuan share in their portfolio.

Explanation of economic cycles, especially stagflation in an oil-dependent economy with high dependency on imported intermediate goods, requires a prototypical representation of the supply side and the propagation mechanism of the external shocks. In commodity-exporting countries, exchange rate changes are often caused by exogenous changes in the terms of trade. Apart from this, external shocks such as international sanctions, restricting foreign trade and increasing transaction costs, not only affect external relative prices but also disrupt the supply chain, thus can be a very strong source of economic cycles or stagflation episodes. External shocks modify investment decisions regarding domestic and foreign assets, significantly affect household consumption and hence the demand side of the economy. Where the final product is highly dependent on imported intermediate goods, negative foreign shocks (i.e. sanctions) can disrupt the supply chain, via the imported intermediate goods channel, and affect output supply price. Therefore, the transmission mechanism of the external shocks in an economy with the above features requires appropriate modeling of both the demand and supply sides. As to explain the observed episodes of stagflation in the Iran’s economy, we expand the supply side of a typical new Keynesian DSGE model by presenting and separating imported and domestic intermediate goods in the production function as components of the supply chain, introducing an extra channel for the impact of external shocks on output, inflation, and consumption.

Energy demand modeling is one of the main challenging issues for energy experts. This study attempts to identify the gaps and differences in the energy demand modeling literature. More specifically it concentrates on the properties of two approaches: "single equation" and "demand system", which are commonly used in this area. Our review indicates that the single-equation approach, despite its simplicity for estimating parameters, suffers from severe problems, such as endogeneity and instability in parameters. However, the serious problem with this approach is that its specification has not been supported by the rigorous microeconomic theory. On the other hand, the energy demand system model is explicitly derived from the microeconomic theory that makes it possible to derive own- and cross-price elasticities of energy fuels and  consider inter-fuel substitution. However, the major problem of this approach is that the demand elasticity estimates are more sensitive to selecting functional specifications. We investigate and compare the properties of the two common functional forms in energy demand systems namely, translog and linear logit model. Our results indicate that the linear logit model, under theoretical regularity conditions, can provide more convenient estimates of demand elasticities compared to the translog functional form.

Prior to the 2008 crisis, economists paid little attention to the role of the bubble and its detrimental effects on the real sector of the economy; But with the crisis, it became clear that the effect of the bubble in asset markets was not limited to nominal effects and could severely affect the real sector of the economy. Accordingly, the main purpose of this study is to investigate the existence of bubbles in the housing market and also to identify the exact time of its origination and collapse. In this regard, using the quarterly data of Tehran housing market in the period 1372: 1 to 1399: 3 and also using the new approach of Philips and Shi (2018), the existence of bubbles in this market was tested. The results of this study indicate that there is a price bubble in the housing market in some time periods in our sample. Examination of the real price as well as the price-to-earnings ratio indicates that there have been periods in our sample that have had very similar characteristics to bubble periods. The results obtained from the Phillips and Shi test also confirm this and indicate that the Tehran housing market has witnessed a price bubble in 1381, 1397, 1398 and 1399. Graphical analysis of bubble collapse periods also shows that after these periods, real prices in the housing market have decreased significantly. This is exactly in line with price behavior in bubble periods and confirms the results of previous tests.

In recent decades, due to the importance of future values of macroeconomic variables, a range of predicting methods and models has been studied and evaluated. The main purpose of this paper is to compare different methods of predicting Iranchr('39')s economic growth using seasonal time series data during 1990-2017. To this end, economic growth is predicted using dynamic model averaging (DMA), dynamic model selection (DMS), BMA, BVAR, TVP and AR models in three prediction horizons (one, four and eight seasons). The models used in this study are categorized into three spectra, large-scale (including 112 variables in nine factor blocks), average-scale (including 10 variables) and univariate models. The results show that the predictions of DMS and DMA are more efficient than other traditional prediction.

More recent research indicates that the effect of monetary policy is state-dependent. This paper conjectures that the impact of monetary shocks on output and inflation in the Iranian economy is contingent on state of the economy, reflecting the size of oil revenue streams, which closely approximates economic cycles. Limited access to international financial markets together with fiscal spillovers emanating from financing of government expenditures and fiscal deficit finance, in a fiscally dominant environment, are the main contributing factors in this respect. To address the state-dependent effectiveness of monetary shocks in the Iranian economy during the period 1990-2017, we utilized a two-stage nonlinear SVAR model. First, the monetary and fiscal shocks were identified by a short term zero-restriction method in which fiscal dominance was taken into account as an amplification mechanism for fiscal shocks. Then, we used a smooth transition auto regressive (STAR) method proposed by Auerbach and Gorodnichenko (2012) to decompose boom and bust oil revenue cycles. Finally, the asymmetric effects of monetary shock on output and inflation in expansion and contraction phases were analyzed by impulse response functions estimated using local projection method developed by Jorda (2005). Our findings demonstrate that the reactions of output and inflation to monetary shocks are asymmetric and state-dependent over oil revenue cycles. While the impact of monetary shocks on output is positive and significant only in the expansionary phases, the positive reaction of inflation to monetary shock is stronger and more persistent in oil revenue scarce periods rather than abundant ones.

Oil price shocks have direct and indirect impacts on the economies of oil-exporting and oil-importing countries. The direct impacts are through demand and supply channels and the indirect (spillover) impacts are through interaction between the countries. Most studies have focused on the direct effects of the oil price shocks in a specific country or a region and research works on indirect impacts are limited. In this research, the direct and indirect effects (spillover) of oil shocks on both groups of oil-exporting and oil-importing countries are estimated using a dynamic system model. The spillover effects are defined and measured by the “Trade Ratio” and “Weighted Average Economic Growth” indicators. The sample includes 30 oil-exporting and oil-importing countries with a share of 73 percent of the world’s economy. The results show that a positive oil price shock reduces economic growth in oil-importing countries and increases it in oil-exporting countries, but international trade between the oil- exporting and oil-importing countries mitigates the impact of oil shocks on economic growth of both groups.

Recent theoretical econometric studies have focused on mixed frequency data. These studies are of great importance since they emphasize the role of information in economic modeling. In the current Time Series approach, temporal aggregation is often turned to a period of identical alternation; however, such aggregation leads to information loss in higher-frequency data. The mixed frequency studies provide a way to avoid the need for such temporal aggregation. In particular, the main result of this branch of econometric studies is to improve explanatory power, prediction, and efficiency in time series modeling with mixed frequency data. Accordingly, this paper attempts to specify the developments and shortcomings of this new branch of econometrics by reviewing the extant literature.

This study examines the impact of a negative shock-attributed to a systemic risk-on the industrial indexes of the Tehran stock market using daily data form 21 January, 2008 to 22 September, 2017. Using a Vector Autoregressive for Value at Risk (VAR-VaR) and a quantile Impulse-response function that was newly proposed by White et al 2015, we focus on the tail interdependence between industrial index returns (financial institutions) and the market shock index and show how each industrial stock risks contemporaneously and dynamically response to systemic market shocks. Our finding show that there is a significant volatility spillover from a systemic shock to financial institutions in Tehran stock market. However as expected the magnitude of its impact is not the same for all industrial index risks. For examples, the impact of its shock on the bank and metal industrial volatilities is more sizable compared to its impact on the others. And finally, the stock market index has a strong and persistence tail dependency with the chemical and petroleum product industries.

Housing price swings have always been under the spotlight for policy-makers and academics. Financial accelerator mechanism (developed by Bernanke and Gertler, 1999) can provide some explanation to these fluctuations. With focusing on the concept of financial accelerator, this paper sheds light on the long- and short-run correlation of housing prices and credit in Iran. We applied a Structural Vector Error Correction Model (SVECM) to housing and credit market over period 1988q2-2015q1. Our findings confirm the existence of a cointegrated relationship between credit and housing prices. In a long-run perspective, the causation goes from credit to housing prices. However, in the short-run we find an existence of contemporaneous bi-directional dependence between housing prices and credit. In general, we find the evidence of housing collateral effect in housing and credit markets in Iran. However, this role is small and limited compared to the same role in countries with developed financial and mortgage markets.

In this paper, we have utilized a time-varying parameter vector autoregressive model in order to examine the structural changes in the transmission mechanisms of oil price shocks in the global crude oil market over the period of 1985-2016. In this setting, the contemporaneous response of real oil price and crude oil production to flow oil supply shock, flow oil demand shock, and speculative demand shocks are explored. Results obtained from using Monte Carlo Markov Chain estimation method along with the identification approach proposed by Killian and Murphy (2014) reveal that the impact responses of oil production to the structural shocks follows a decreasing trend throughout the past three decades mainly due to the erosion of global oil production spare capacity. The reaction of oil production to flow oil supply shock is also estimated to be greater than other demand shocks over all dates. Moreover, the contemporaneous impact of structural shocks on real oil prices fail to show a clear pattern, however, jumps experienced in periods where uncertainty heightened and risk aversion strengthened is distinct. The reaction of real crude oil price to flow oil supply shock was more pronounced in 1990s and the period subsequent to oil price plunge in 2014. By contrast, the role of flow oil demand shock in real crude oil price fluctuations was dominant over the period of 2000-2014. While the oil production reacted more strongly to speculative demand shock rather than flow oil demand shocks, the response of real oil price to these two oil demand shocks is completely reversed

Significant decline in the slope of short-term oil supply and demand curves, along with the meaningful change in the degree of risk aversion in arbitrageurs encouraged us to test the time-varying effects of speculative demand on crude oil price dynamics over the period 1985-2016. Using a time-varying parameter vector autoregressive (TVP-VAR) model – with structural shocks identified by Killian and Murphy (2014) approach – we estimated contemporaneous impulse response of real oil prices and crude oil production to speculative demand shock; Furthermore, we derived short-term price elasticity of oil supply in response to speculative demand shock and short-term price elasticity of demand in use. The results demonstrate that the contemporaneous impact of speculative demand shock on oil production has weakened over the examined period of time. Despite moderately stable impact response of real oil price to speculative shocks, the jumps during the periods of high uncertainty and stronger risk aversion are discernable. Moreover, short-term price elasticity of oil supply in response to speculative demand shock, followed a downward trend in a pattern that was always greater than short-term price elasticity of oil supply in response to flow demand shock. The price elasticity of respective oil demand in use was also decreasing and it was smaller than The price elasticity of oil demand in production over the period. Furthermore, the magnitude of speculative oil demand shock volatility plummeted during 1985-1995, before it became stagnant in the succeeding years.

Following oil price shocks, “Expenditure Effect” is one of the most important and influential channel affecting the oil exporting economies. The magnitude of the structural shock effects on oil exporting economies depends on the type of the shock and government expenditure in the economy. In this study, using quarterly data from 1988 to 2014 of Iranian economy and global oil market, first, in line with kilian (2009), supply and demand shocks are disentangled and identified and then, using a dynamic factor model (with the Bayesian approach), which is unlike the standard autoregressive models not suffered from the reduction of degree of freedom due to inclusion of new variable, the impacts of oil price shocks on relevant expenditure variables are investigated. The findings indicate that the response of public and private expenditure variables to the structural shocks in the global oil market is different. The positive global real activity shock affects domestic economy through two channels, an increase in oil revenues, and a boom in the domestic economy which increases private consumption, including durable and non-durable goods, services, total import, and total investment. The effect of this shock on public consumption is instantaneously negative and it becomes statistically insignificant after one period. Since the impacts of oil market-specific shock only increase oil revenues, it affects public consumption positively and statistically significant but do not affect private consumption and total investment. The effect of this shock on total import is instantaneously positive although it dies out after one period.

In this paper, we investigate volatility transmition between four precious metal (gold, silver, platinum, palladium) using a multivariate GARCH model. We also investigate effect of shocks on precious metals using volatility impulse response function.
The results of the VAR (1) -BEKK (1,1) using weekly data estimated price is four precious metal, showed relatively high correlation between yields and volatility of these metals with each other there. Also, the analysis of the volatility impulse response Function Graphs of four precious metals showed that the gold and silver volatility had almost the same behavior in the face of the impasse of the financial crisis of 2008. The results of this research, especially for investors in global markets, can be very important.

The economy of Iran has witnessed a couple of booms and busts in housing prices over the period of 1981(1)-2014(4). Since the fluctuations in housing prices affect household wealth, and consequentially, total consumption, saving and even banking, it is of crucial importance to analyze the impact of such fluctuations on real economy. This study, utilizing the MSIAH -VARX model, examines booms and busts in housing prices in Iran over the aforementioned period. This approach offers the possibility to identify different regimes in Iran’s housing market. Moreover, the probability of staying in one regime as well as that of transition from one regime to another could be estimated. The findings indicate that during the aforementioned period, there are two regimes of boom and bust in housing prices. Furthermore, the probability of staying in a bust regime is greater than that of a boom regime.

Energy is one of the most important influential factors in every economy. Energy is used as an intermediate input by firms, as a final commodity by households, and transportation costs are heavily dependent on energy. So analyzing the impacts of energy policies on the economy is very important. One of the common energy problems in many developing countries is energy subsidies. According to IEA, energy subsidy is any government action that lowers the cost of energy productions, raises the price received by energy producers or lowers the price paid by energy consumers. The most common reasons for the introduction of energy subsidies are lowering the cost of production, and consumption and alleviating energy poverty. However, despite some limited benefits, energy subsidy can leads to market distortion, substitution of energy with other production factors, increasing of energy consumption, reduction of incentives for energy efficiency, imposing fiscal burden on government budget, reduction of investment on other technologies of energy production, smuggling of fossil fuels, and environmental emissions. Therefore, reform of inefficient subsidies has the potential to provide substantial gain for the economy, and due to this reason, many countries, including Iran, started energy subsidy reform. Energy policy reform in Iran is multistep reform that the first phase of it began in December 2010, and other phases are going to be implement in the coming years.
Energy policy reform might have considerable effect on income distribution. Since income inequality might cause serious social, political and economical problems, the policy makers should consider the inequality effects of this policy reform. In this paper we analyze the effects of reducing energy subsidies on income level and income distribution in Iran. Analyzing the effects of exogenous policies and shocks on income distribution requires a method that incorporates both aggregate impacts on the economy and the heterogeneity of the effects on households. We used a computable general equilibrium model with heterogeneous households for the study of the effects of reducing energy subsidies on income distribution. This method provides a possibility to simulate the macro and intersectoral effects of exogenous policies, and the heterogeneous effects of policies on households as well. In order to incorporating heterogeneity of households into the computable general equilibrium (CGE) model, we disaggregated household sector in social accounting matrix into 100 rural and 100 urban representative households based on expenditure per capita. Then we estimated the parameters of households demand functions using micro database of household survey data, and then we construct and simulate the CGE model.
In terms of macroeconomic results, the simulations show that energy subsidy reform have decreasing and increasing effects, respectively, on GDP and inflation. In terms of distributional results, one of the advantages of the CGE model with disaggregated households by percentile of expenditure per capita is direct calculation of Gini coefficient. If the policy simulation increases Gini coefficient, then the policy can be thought regressive, and if it reduces Gini coefficient, it can be regarded as progressive. The simulation results show that lowering energy subsidies could have decreasing effect on real consumption of urban and rural households for all income quintiles, such that it reduce consumption of urban household more than rural one, and as we go to higher income percentile this decreasing effect increase with decreasing rate.

This paper develops a dynamic general equilibrium model (DGEMI) for evaluating energy policies in Iran’s economy. DGEMI provides a detailed multisector framework for analyzing economic transition, removal of energy subsidy, and technological change policies. The results show that eliminating energy subsidies (once- for -all or gradually) in the absence of technological progress is in itself insufficient to stimulate the investment and economic growth. Although the energy intensity along with this policy declines over time, its decline can not be attributed to the energy efficiency, since the economy falls into the lower level of new steady state after removing the energy subsidies. On the other hand, the combination of eliminating energy subsidies and technological progress policies provide a strong growth stimulus accompanied by a pronounced increase in productive efficiency and a decline in intensive energy.

Indicators of water resources status and water consumption in Iran reveal an imbalance between supply and demand. This is compounded by the current unrealistic water price that signals the inefficiency of the water market in Iran. In economics parlance, the most important factors responsible for the low efficiency of water market are inaccurate valuation and failure to define the ownership rights of water. Low prices, low sensitivity of water demand to prices, and the lack of proper inputs as substitutes for water resources have collectively contributed to excessive pressures on the available water resources for domestic, industrial, and agricultural uses. A brief glance reveals that water resources in Iran are merely priced based on cost accounting. This is while study has shown that developed countries adopt approaches to water pricing that not only consider the final cost of water but also take into account such other parameters that are affected by intrinsic value of water including its bequest and existence values. The present paper draws upon the concepts of value, expenses, and pricing of water in an attempt to explore the marketing and pricing of water resources as the two major tools economists employ in the management of these resources. It is the objective of the study to arrive at an accurate definition of ownership rights of water resources to improve upon the present water marketing. In doing so, the more important components of modern pricing strategies adopted by developed nations will also be investigated. Results indicate that the present cost accounting method used in pricing water in Iran will in the long-run lead to the wastage of water resources and that it should, therefore, be given up in favor modern and more realistic policies to avoid such waste of resources.

The present paper investigates the impact of an oil shock on the Iranian macroeconomics activities from a general equilibrium perspective. We address a new evidence of the reallocation of oil resources between public and private sectors in an oil exporting country. Our finding indicates that while a positive oil shock expands the public sector (investment, capital stock, employment and production positively responded to the shock), the private sector has become smaller following a positive oil shock. In general, we find the strong signs of crowding out effects of public over private investment after expanding the public sector due to a positive oil revenue shock.

The aim of this paper is to identify the bubble of housing in Iran. For this purpose, the base price of housing will be estimated at first and then the bubble calculated as the difference between the base and actual prices of housing. Considering the rationing in the mortgage market of Iran, the equation of housing real prices is used. In addition, to create an index of mortgage rationing, mortgage rationing model is used by some changes. The data are seasonal related to 17 metropolitan cities in Iran. The results of estimating the mortgage rationing model indicate an inverse relation between the mortgage demand and housing prices. The results obtained by the estimation of real housing prices equation point to the presence of bubble in the housing market. In fact, the burst of housing bubble in Iran is observed in housing market in 1996, 2002 and 2007.

The purpose of this study is to evaluate and compare volatility and spillover effect among oil, Gold and exchange rate (US Dollars-Euro) markets in last decade and the decade before 2003. Using weekly data from 1993 to 2012, this paper employs econometric methods like M.GARCH-ASY-M (Multivariate GARCH Asymmetry Mean) and BEEK model to estimate the volatility magnitude and spillover effects in markets mentioned, Results show the relationship between markets and their power for risk transferring is significantly affected by the news and volatility persistency in a market. The persistent increase in oil prices after 2003 causes a significant relationship between returns and augmentation of spillover transferring among oil, gold an exchange rate markets. So, this finding show how the news and information among markets can augment the relationship between returns and risk spillover magnitude. Finally, the strength of effects depends on the persistency of news flows from one market to another.