جستجوی مقالات مرتبط با کلیدواژه « منحنی S » در نشریات گروه « اقتصاد »

The purpose of this paper is to evaluate the role of ICT due to ecological footprint from the perspective of individual effect and the trend of the 113 countries' reserves and land production in selected developing countries using the data panel method in the period 1992-2018. The results showed that increasing the mobile penetration rate increased greenhouse gas and carbon dioxide emissions and increased the ecological footprint effect. However, increasing the Internet penetration rate has reduced carbon dioxide emissions, increased greenhouse gases, and increased ecological footprint. Therefore, ICT use in these countries has not yet been effective in improving the environment. In the short term, there is a positive relationship between economic growth and environmental degradation in these countries, and economic growth worsens the quality of the environment. And in the long term, there is evidence of the Kuznets hypothesis being correct. Dynamic analysis showed that the use of ICT has been effective in improving the environment and this effect lasts for at least a decade. Technology shocks have an immediate effect on improving some environmental indicators and the range of effects on some indicators appears in the long term. In these countries, the production of ICT has no relative advantage, but they can benefit from the economic and environmental benefits of ICT.

One of the most important economic problems in Iran during the last few decades is the phenomenon of high and double-digit inflation. So, improving the conditions caused by high inflation has always been one of the important goals of the country's development programs. Achieving this goal requires the creation of a precise and targeted mechanism in the economic policy-making process. In its standard form, it includes forecasting, goal setting and policy analysis. The general purpose of this study is to predict the inflation rate using economic variables that affect it. In this research, the Bayesian averaging method is used to investigate the best estimation model that can predict the inflation in Iran. In this regard, the previous studies conducted in this field are first reviewed, and then the most important economic variables affecting the inflation are identified and used to predict the inflation rate.

Friedman believes that inflation is always and everywhere a monetary phenomenon. Monetarists believe that inflation comes from the disproportionate growth of nominal money supply. So, the higher this growth, the higher the inflation rate is. There is a direct and proportional relationship between money growth and inflation. According to this theory, changes in money supply have no effect on real variables such as production, employment and real wages; they only affect nominal variables such as prices and nominal wages proportionally. Monetarists consider the real growth of the economy in the long term to be independent of the change in the money supply and generally believe that this growth is determined by factors such as production capacity, increase in labor force due to population growth, advancement of technical knowledge and natural resources.In order to control or curb inflation, the influencing factors must be identified. The results of the studies on the factors that cause inflation are different or even inconsistent, because it is based on the researcher's specific attitude. In this article, to avoid falling into such a vortex, the Bayesian averaging method is used to predict inflation. The seasonal data of 1990-2022 have been used to predict the inflation rate in Iran.

Forecasting inflation is one of the most important but difficult issues in macroeconomics. Many different approaches have been proposed in this field. Perhaps the most popular of these approaches are those based on the Phillips curve. However, the general framework includes a dependent variable such as inflation (or change in inflation) and explanatory variables such as inflation breaks, unemployment rate and other predictive factors. Meanwhile, return and regression-based methods have been somewhat more successful.The results show that dynamic model averaging leads to significant improvements in forecasting compared to other approaches such as OLS, ARMA, and ARDL. Also, among the variables influencing inflation, the most influential for predicting the inflation rate relates to household consumption expenditure, unemployment rate, and workers' wage rate.

Conclusions and policy implications: 

The general purpose of this study was to predict the inflation rate using the economic variables that affect it. In this research, the Bayesian averaging method served to investigate the best estimation model that can predict the inflation in Iran. In this regard, the previous studies conducted in this field were first examined and then the most important economic variables affecting the inflation were identified and used to predict the inflation rate. For this purpose, the seasonal data of the variables during the period of 1990-2022 were used. In this research, the methods of ordinary least squares (OLS), auto regression moving average (ARMA), auto regression with distributed lag (ARDL), Bayesian dynamic averaging (DMA) and Lasso regression were used to predict the inflation and evaluate the prediction accuracy.Therefore, based on the results obtained in this research, attention should be paid to the behavioral economic parameters of households when choosing the optimal policy. Factors such as the increase in household food prices, the high increase in workers' wages, the increase in money supply, the increase in interest rates and the increase in residential rental rates have definitely caused the formation of inflationary expectations in the society and can cause instability in the future and make the inflation deviate from equilibrium. Thus the measures to take include controlling the household food market, controlling the housing market, reforming the wage pattern in the country, controlling the interest rates in banks, and using contractionary monetary policies. These help to control and reduce inflationary expectations among the people.

This study evaluated a relationship between macroeconomic variables and the yield curve in Iran between years 1994:q1-2016:q4 using a dynamic stochastic general equilibrium model. The model consists of the household, the firm, the finance, the oil, the government, and the central bank. Both households and firms have the exclusive power to supply their labor and their products to adder, which makes it possible to stipulate nominal rigidity  in   wages and prices. After optimizing and obtaining the first order conditions of the brokers, using Uhlig method, the linear - log shape of the equations were obtained. The results of the impulse response functions indicates that the preliminary effect of the technology, monetary, and oil shocks on the slope of the Islamic treasury bills yield curve is positive, the preliminary effect of the technology, government expenditure, and cost push on the curvature of the yield curve is negative, and the preliminary effect of the technology, government expenditure, and cost push on the level of the yield curve is positive. The comparison of the moments of the model variables and the moments of the actual data of the Iranian economy reveals the success of the model in simulating the realities of the Iranian economy.

The purpose of this article is to evaluate the effects of information and communication technology on the quality of the environment (publication pollutant gases, carbon dioxide and greenhouse gases) and ecological footprint (from three aspects of the effect individual, country reserves trend and land type) in member countries of the Economic Co-operation and development  Organization is using the panel data method in the time period of 1992-2018.The results showed Expanding the use of ICT  in the mentioned countries has a positive effect on improving the quality of the environment And It has reduced the emission of carbon dioxide, greenhouse gases and ecological footprint.Furthermore, the consequences of ICT on the quality of the environment in the long term have been more than in the short term. Therefore, the findings showed that the substitution effect of ICT (substitution of online activities) compared to Income effect (increased leisure time from the substitution effect and increased travel demand) in the case study has been dominant.

Afghanistan's trade balance has been in deficit for many years, especially in the last two decades, and the deficit has always been covered by foreign aid and the Central Bank's foreign exchange reserves. The assessment, which is considered one of the most important changes in the creation of international relations, will lead to the improvement of the trade balance in order to create a framework and use appropriate currency policies. This experimental research aims to investigate the J-shaped curve phenomenon in Afghanistan's trade balance with its largest trading partners, which uses the Panel-ARDL econometric method to estimate price and income factors. The data used in this research is composite and it has studied the period from 2008 to 2018 along with twenty-one major business partners. The model outputs include the real exchange rate, Afghanistan's GDP, and each partner's GDP. In order to analyze and estimate the long-term and short-term relationships of Afghanistan's trade balance, the co-accumulation and ARDL tests were used. The research investigations, with the disconfirmation of the J-curve effect in the short term, have indicated the positive and meaningless effect of the exchange rate, and in the long term, the price factors (exchange rate) have a greater effect on the trade balance than the non-price factors (GDP). Also, on the other hand, the internal business relations of short-term partners have significance in the long-term. After estimating the model, it is concluded that devaluation policies in improving trade depend on the mutual behavior of trading partners and their currency stability.

The trade-off between inflation and the output gap is different under each of the specifications of the Phillips curve, and therefore the optimal monetary policy will be different based on the assumption of each of these specifications. Considering the importance of the issue, and in order to identify the Phillips curve compatible with the stylized facts in the Iranian economy, by implementing the framework of the Dynamic Stochastic General Equilibrium (DSGE) model and Bayesian analysis, a wide range of pricing models including sticky information, Dual-stickiness, generalized Calvo, multi-sector and hybrid models have been compared and evaluated. To compare different pricing models in this study, four criteria have been applied: comparing the posterior probability of the models, comparing the moments of the simulated data of the model with real data, comparing the autocorrelation of the real inflation rate with the median of the posterior distribution of each of the models, and examining the impulse response functions. According to the results, the Phillips curve under Dual Stickiness is more consistent and compatible with the stylized facts in Iran's economy, compared with other Phillips specifications. In specifying the Phillips curve under Dual Stickiness, in addition to the expected inflation component, the lag of inflation also appears endogenous (due to the simultaneous assumption of two types of price and information stickiness).

Government activities in an economic system play an important role in the country's economic growth and development, but increasing the volume of these activities to certain thresholds has a positive effect on economic growth, and from that threshold, increasing in the volume of government activities not only has no positive effect on economic growth, But these activities are the main obstacles to growth. The explanation for the non-linear effects of government expenditures on economic growth is known as the Army Curve. In this study, the relationship between government expenditures and economic growth has been investigated by using Army curve in Iran and South Korea (1990-2015) and with using autoregressive distributed lag model. The results show a positive nonlinear relationship between government expenditures and economic growth in both Iran and South Korea. With the negative sign of the power factor of the second government expenditure, the existence of a logistic curve in the long run is evident for both oil exporter and importer country: Iran and South Korean

In most countries, taxes are the most important source of government revenue. But in Iran, taxes have long provided a small share of government revenues. Perhaps the most important reason is the existence of oil revenue sources that have put the tax on the sideline. For this reason, the emphasis has been on reforming the tax structure. In this regard, the Law on Value Added Tax was implemented in Iran in the second half of 2008 to reform the tax structure. VAT is a new tax that was created to reduce the shortcomings of the traditional tax system and also to increase government revenue. VAT is a type of sales tax that is levied at various stages of production and distribution of goods and services. The average VAT rate in different countries is between 5% and 18%. In Iran, since the enactment of the VAT law, there has been a lot of controversy and debate among experts regarding the determination of tax rates. This rate was set at 3 percent at the time of implementation of the VAT law and was set to increase by one percent each year, so that in 2018 it reached 9 percent. As the tax rate increases, so does government revenue from tax collection. However, this increase in income is limited, and if tax rates exceed a certain point, tax revenues will decline, because due to high tax rates, people will lose motivation to work. Therefore, it is necessary to determine the tax rate that maximizes tax revenues. It is also necessary to determine the optimal rate of this type of tax so that the government's tax revenue is maximized but it does not hinder economic growth. The present study was conducted for this purpose.

This research was conducted in the period of 2008-2018 using data from 24 provinces whose information was available. The research data related to VAT rate and government tax revenue in the period of 2008-2018 was collected from the provincial yearbooks. The year 2008 is the beginning of the implementation of the VAT law and 2018 is the last year that information and statistics were available. Finally, the optimal VAT rate in Iranian economy was estimated using data panel method. In this method, first, using Lemmer test, panel data in model estimation was selected. Then, using Hausman test, the estimation with random effects was confirmed. All analysis and model estimations were performed using EViews 9 software.

Findings from the statistical description of the data show that VAT rate in Iran in 2008 was set at 3% and remained at the same rate until the end of 2010. From 2010 onward, VAT rate increased so that in 1394 it reached 9%. From 1394 to 1396, it remained constant. Also, the results of model estimation show that VAT in Iran has lufferel effects; i. e, increasing VAT rate directly increases the government's tax revenue and indirectly reduces the government's tax revenue by reducing production incentive. Therefore, VAT rate has an optimal value at which the rate of government tax revenue is maximized.

The optimal VAT rate calculated in this study is 10.33%. Considering that VAT rate has been set at 9% in 1398, increasing this rate to 10.33% in the coming years is recommended. This will increase the government tax revenue. An increase in the tax rate above this amount will reduce the government tax revenue. Therefore, exceeding VAT rate over 10.33% is not suggested.

Institution of the family, its functions and welfare in Islam have a special place. The share of food costs in the total household expenditure is one of the indicators of welfare and increasing the household dimension as one of its functions is affects this index. In this regard, the purpose of this study is to investigate the factors affecting the share of urban and rural households' food cost with emphasis Islam's approach to the household dimension using the least weighted least squares method  and income and expenditure data of 9578 households in Isfahan province during the period (2006-2014). The results show that with the increase of the total household cost and the change of housing of households from rural to urban, the share of food costs decreases. Also, with the increase of the household dimension and the increase of the age of the head of the household, the share of food costs in the total cost of households has increased and has led to a decrease in household welfare. Accordingly, the government should apply different support policies to increase the level of welfare of households according to the size of the household, the age of the heads of households and their place of residence.

In recent years, economic complexity has played an important role in explaining and revealing the latent facts of the difference in economic growth among the poor and rich countries. In this study, first the effect of economic complexity on environmental performance is investigated in 18 countries of Middle East and North Africa(MENA) using two-stage least squares regression(2SLS) method during 2002-2018. Then, the Environmental Kuznets Curve hypothesis is examined in these countries. The results show an inverse and significant relationship between economic complexity index and environmental performance index, so that by increasing one unit of economic complexity index, environmental performance index decreases by more than 7 units. In addition, the results show that there is a positive relationship between per capita income and environmental performance index, while per capita income square has an inverse relationship with environmental performance index, so Kuznets hypothesis about these countries is not confirmed. Finally, the results indicate a positive relationship between population, urbanization, corruption control, agriculture and trade with environmental performance, while industrialization and education have a negative relationship with environmental performance in the MENA countries.

The purpose of this article is to evaluate the intensity of learning in the Iranian banking industry during the period 2001 to 2016. During the period under review, the Iranian banking industry consisted of 10 state-owned banks and 17 private banks. In order to evaluate the realization of learning in the Iranian banking industry, a Cobb-Douglas cost function was used. In this function, loans and facilities were considered as inputs as well as labor, capital and bank deposits as inputs. After adjusting the cost function, this function was converted into a learning curve and then the learning curve was estimated. In the learning curve, the cumulative amount of loans and facilities was used as an indicator of experience. The results indicate that the slope of the learning curve is in line with negative expectations, which is as if learning has been achieved in the Iranian banking industry in the period under study, but its intensity is low. In addition, the results indicate a constant return to scale in the Iranian banking industry.

Poverty is a fundamental multidimensional phenomenon which has always been and is one of the most important detriments to societies and the root of the problems and hindrances of most parts of the world. Efforts to eliminate this social problem are one of the most prominent goals of economic growth and development; and despite economic growth in underdeveloped or developing countries, this problem persists. .Although growth in income, as one of the macroeconomic variables, has a significant effect on poverty and its reduction, but the existence of inequality and its effect on economic growth plays an important role in benefiting the poor from economic growth. In the process of economic growth, what reduces poverty is an increase in household income; thus, the distribution of income among households should be such that the poor also benefit from this growth. Therefore, economic growth is not sufficient to eliminate poverty on its own, and its effect on poverty is not the same at different times and places, and the manner in which the benefits of growth are distributed is significant as well. Inequality and poverty are two completely different concepts, but they are deeply related. Therefore, paying attention to economic growth and reducing inequality can have good results in reducing poverty. In recent decades, societies that have focused on both economic growth and reducing inequality have been much more successful in reducing poverty. In this regard, to understand the effects of economic growth on poverty, it is necessary to distinguish between the effects of economic growth on poverty and the effect of inequality on poverty. Then, the change in the poverty index is broken down into a change in average incomes and changes in income inequality to properly determine the contribution of income and inequality in poverty decrease.

in the present study, the effects of income and inequality and their resultant on reducing poverty in the provinces of Iran over a fourteen-year period, from 2004 to 2018, have been determined using the Sen Index, the Kakwani method, and various mathematical methods.

As confirmed by our study results, both income effects and inequality effects had performed in favor of the impoverished in the province of Yazd and led to poverty reduction, while in Kermanshah, Khorasan Razavi, Isfahan, and Zanjan the income effects and inequality effects have somewhat neutralized one another. In other words, even though the increase in the average income reduced poverty, the increased inequality led to increased poverty. On the other hand, the situation in the province of Alborz was considerably different. In this province, although decreasing the average income increased poverty, the improvement in income distribution not only eliminated the negative effects of the income share, but also reduced poverty. However, the income effects and inequality effects had moved in the same direction in Gilan, Khuzestan, Fars, Hamedan, Chaharmahal & Bakhtiari, Lorestan, Tehran, Qom, North Khorasan, and Sistan and Baluchestan, to increase poverty. Finally, in other provinces, the distribution of income has changed in a way that despite the increase in average incomes, poverty increased.

Therefore, as the research findings show, poverty has decreased in only a few provinces during the period under review. And the inequality effects and the income effects, or both, have led to increased poverty. Therefore, in order to reduce poverty, economic growth and reduce inequality must be given much attention.

In this study, the extent of self-employed households' income under-reporting is estimated based on the expenditure approach, using household budget data. In this regard, the Engel curve of wage earners, which represents the relationship between their income and food expenditures, is used to estimate the true income of self-employed households based on their stated food expenditures. Through this approach, the average under-reporting of self-employed households during 2000 to 2019 equals 8.5 percent of their total income. By examining under-reporting among different groups of jobs, it can be observed that the highest under-reporting is among the "agriculture, forestry and fishery skilled workers" and "legislators, high-ranking officials and managers". Then, in order to study the temporal under-reporting behavior, it is estimated separately for different years. The results show an ascending trend in the extent of under-reporting during 2004-2010, in a way that this extent reaches its highest point in 2010. 

Knowledge development and accumulation are important sources of economic growth and development and Learning is one of the effective factors in the development and accumulation of knowledge. Learning reduces the average cost over time along with increasing cumulative production. The chemical industry plays an important role in the country's economy due to its high value added, product diversity and employment. The objective of this study is to analyze learning by doing in Iran's chemical industry at the level of four-digit ISIC codes using panel data during the period 2011 to 2015. For this purpose, the learning curve was estimated using the panel data technique, assuming a constant return to scale. The finding indicate that learning has been achieved in Iran's chemical industry and the slope of the learning curve, ie the effect of learning in all sub-sectors of Iran's industry, as expected, is negative and equal to 0/86. The results indicate that the learning effect is different in the sub-sectors of Iran's chemical industry, but it is close to the average learning intensity.

Wealth distribution is one of the most important and effective factors in the economic and social stability of each society. Thus, assessing the behavior of income distribution have great importance and to do this, several indices have been introduced that their performance has been investigated in terms of precision. The main goal of this paper is to introduce the Total Time on Test (TTT) transformation and its corresponding graph as a beneficial index for measuring income inequality. We further compare its performance with the Lorentz and Zanga indices. The micro-data of Iranian household income in the period 2012-2018 has been used to analyze the performance of the proposed index. The results show that while the new index performs better than the Lorenz one, it performs as same as the Zenga index. We also introduced a new distorted model using distortion functions in the final section, and by considering the basement income distribution, the generalized version of these distributions are presented and some of their features, particularly the maximum likelihood estimator are investigated. In addition, the goodness of fit of the new distributions to the income data of citizens in Texas (Arnold 1983) and the income data of Iranian households in 2017 are other results of this article.

Economists believe that free trade with the export of domestic goods and the import of goods from abroad increases the welfare of the countries. Therefore, improving trade is one of the major economic goals of any country, and free zones are developed in line with the development of exports and imports, the acquisition of currency revenues, and the establishment of a systematic link between the national economy and the global economy. This research seeks to investigate the effect of exchange rate, as an effective variable on international trade, in the form of a J-curve on trade in trade-based cities of Iran. Therefore, this effect is estimated for the trade-based cities of Kish, Qeshm, Chabahar, Anzali, Arvand, and Aras during the 2005-2017 period, using a PANEL ARDL. The results indicate that the effect of the exchange rate on exports is not significant in the short term, but in the long run the effects is significant (58.02). This effect on imports is significant and 565.05 in the short term and 381.1 in the long term. Therefore, although the short-term and long-term effects of the exchange rate on exports, imports and the trade balance of these cities are positive, but the long run the effect of the exchange rate on exports and trade balance is stronger than its effect on the imports. So this evidence confirms the existence of a j-curve in Iran's trade-based cities in the long run. Thus, the realization of the exchange rate, in long term, can ultimately encourage the exports and reduce the dependence on the, and thus improve the trade balance of the cities. Therefore, the findings of this study can be a useful for economic decision makers and policy makers in managing coastal cities.

The topic of poverty has always been studied in the world. If we can break down poverty, we will have a better understanding of the changes in poverty .The purpose of this article is to show the status of poverty and its three dimensions in chronic and transient poverty in Iran using the raw data of the Iranian Statistical Center and drawing the three dimensional curve of poverty (TIP) using the Jenkins and Lambert (1997) method, the poverty status and its dimensions in Iran were studied and then followed by Chakravati et al .chr('39')s (2008) new analysis of the two components of chronic poverty and transient poverty and their extraction from total poverty over an 11-year period in the Iranian economy since. It was done from 2007 to 2017. Finally, the effect of three dimensions of poverty on chronic poverty and transient poverty was calculated based on Shapleychr('39')s method The results obtained from Income Poverty show that at any given time, nearly 60 percent of Iranchr('39')s population is below the poverty line. Poverty intensity is 0.54 and income inequality among the poor is 0.34 .Chronic poverty accounts for 84 percent of total poverty in Iran. Also, the share of poverty incidence and the intensity of poverty and inequality among the poor on chronic poverty are 47%, 35% and 18%, respectively. and the share of the three dimensions of poverty on transient poverty is 65%, 7%, and 28%, respectively. Chronic poverty is strongly affected by poverty incidence and the intensity of poverty and transient poverty is more affected by poverty incidence than other dimensions of poverty.