نشریه اقتصاد و الگوسازی
پیاپی 39 (پاییز 1398)

After World War II, countries have used sanctions against target countries instead of military attack in order to force them to change their policies. Following the revolution, Iran was sanctioned by the U.S. and its alliances. The strict sanctions imposed on Iran in 2012 and most of them were supposed to be lifted in 2016 by United Nations, following the Joint Comprehensive Plan of Action. Since sanctions can affect countries' economic conditions, specifically their foreign trade relations, it is crucial to study the effectiveness of sanctions. Hence, this study compares the structural economic position of Iran in the international trade network in 2012 and 2016 and investigates the effectiveness of international sanctions on Iran's structural position in the International trade network. Results show that Iran is not only a periphery in the international trade network, but also its structural position in the international trade network is not affected significantly by the sanctions.

Exchange rate and foreign exchange policies in Iran have always been one of the main challenges of the country's economy. Almost in all periods, various and challenges were about how the exchange rate is determined and what will be its effects on economic variables, especially foreign trade and balance of payment. In this regard, the present study examines the effect of the real exchange rate on the trade balance between Iran and one of its largest current partners, China, using the nonlinear symmetric method over the period of 1993-2016. The results show that on the one hand, the most appropriate method in such studies is the use of asymmetric and nonlinear models. On the other hand, the increase of the exchange rate, which is the depreciation of the Rial against the Yuan, improves in the long-run and shor-run, although its long-term effect has been more than its short-term effects. But the depreciation of the Yuan makes the balance in favor of China, as well as the effect of the depreciation of the exchange rate more than its effect on the trade balance between the two countries. Therefore, it is suggested that the realization of the value of the Rial against the yuan and allowing the depreciation of the national currency in line with inflation and other indicators would increase the competitiveness and expand foreign trade.

This paper examines the role of different exchange rate regimes and financial structures on nexus between  exchange rate volatility on economic growth. The main goal is that, despite the fact that the exchange rate volatility can negatively affect the performance of macroeconomic variables, the financial structure, like a channel, can change the effect of these volatility. To investigate this relationship, information of 53 countries with floating and fixed exchange rate regimes in the period of 1980-2016 are considered. GARCH technique is used to estimate exchange rate volatility and Difference GMM technique for estimating the model. Based on the results of the estimation for the whole of the selected countries, the financial structure has a positive and significant effect on economic growth and decreases the negative effect of the exchange rate volatility on economic growth, but with a separate estimate for countries with fixed and floating exchange rate regimes, The results indicate that the financial structure index has a positive and significant effect on the economic growth of countries with floating exchange regime. Therefore it can be argued that countries with floating exchange rate regime in the long run with the transfer of the financial system from the bank-based to the market-based can prevent the adverse effects of exchange rate volatility, but for countries with fixed exchange rate regime, has no significant effect.

Iran is one of the countries with high energy consumption per capita in the world. One solution to reduce energy consumption while increasing economic growth is to improve energy efficiency in various economic activities because increasing in energy savings is one of the eligible effects of the policy of efficiency increase. Improving energy efficiency in the economic activity is a way to reduce energy consumption and enhance economic growth, but the desired effects of the policy are limited due to rebound effects. One of the challenges is decomposition direct and indirect rebound effect and economy-wide rebound effect. The purpose of this article is to provide a theoretical model for the analysis of rebound effects and its calculation in various activities using a general equilibrium model. Based on the results of the modeling, which uses the data of the Social Accounting Matrix of 1390 in Islamic Parliament Research Center , the total direct and indirect rebound effect of increasing one percent of efficiency of electricity and fossil fuels are 90.1% and 72.8%, respectively. The economy-wide rebound effect are also not significantly different from the direct and indirect rebound effects, as households do not respond very well because of the low contribution of energy costs from household expenditures, and so economy-wide rebound effect are 89.9 and 72.5. The high rebound effects observed in the Iranian economy will limit the effectiveness of the efficiency-enhancing policy on reducing energy consumption, so pricing policies along with the efficiency-enhancing policy are recommended.

There are many researches about the role of institutions in different aspects of economic performance. However, in the context of institutional analysis, the issue of technical efficiency has been neglected. This paper investigates the role of institutional quality in the technical efficiency of selected countries in Asia and the Middle East using the stochastic frontier analysis (SFA) approach over the period 1996-2017. By adopting the maximum likelihood estimation (MLE), the estimates associated with the production function and the technical inefficiency equation have been obtained. The examination of technical efficiency based on institutions was carried out in accordance with the Battese and Coeli’s (1995) and Green’s (2005) model in the form of Cobb-Douglass function and using Institutional indicators of governance and then institutional indicators of CIRI. Estimates in both cases represent the fact that a significant part of the technical inefficiency was due to the weak and undesirable qualities of the governing institutions of these countries. Moreover, the estimated results show that inspite of the balanced situation in production inputs, due to institutional weakness among selected countries, Iran is the most inefficient country in terms of technical effeciancy. This empirical finding further emphasizes the need for institutional reform.

The main objective of this study is to compare the Harvey Logistic Growth Models, Harvey, Nonlinear Autoregressive Neural Network, and to design an optimal model with better predictive accuracy for the exchange rate with high volatility and a nonlinear motion patterns which has been neglected for predicting the exchange rate in Iran.  In this study, we use the "Harvey Logistic" Growth Models, Harvey and adding a nonlinear component based on the Taylor series expansion for trigonometric functions, and using the daily data during 1392:1-1398:3, the fluctuations of the exchange rate and the accuracy and prediction of these models are compared its results with the nonlinear autoregressive neuronal network. The results of unit root tests represent that the data is stationary and has nonlinear property. In the estimation stage, the goodness of fit for the Logistic and Harvey models are not confirmed. By adding nonlinear parts to the Harvey model, a good fit was obtained for the exchange rate with a coefficient of determination about 99.95 percent and a minimum mean square error, even when compared with the nonlinear autoregressive neural network. The results show that combining the Harvey model with the nonlinear component is considered as one of the best models which predicts the exchange rate better than other models.

The main purpose of this paper is to examine the effects of financial integration on macroeconomic volatility in Iran. Economic theories do not clearly explian the effects of financial integration on macroeconomic volatility and this is essentially an empirical problem. Hence, we have presented an empirical model to test the effect of international financial integration on macroeconomic volatility in Iran over the period 1352-1395. For this purpose, first, the macroeconomic uncertainty was extracted using stochastic volatility model with leverage effects and using the principal component analysis method. The results show that in the long run, international financial development, international financial integration and terms of trade volatility have a positive effect on macroeconomic volatility in Iran, while the effect of trade openness on macroeconomic volatility in Iran is negative. In addition, in the short run, there is no significant relationship between the relevant variables and macroeconomic volatility.

Unemployment is one of the major economic problems of countries and its decline is always on the focus of researchers and policy makers. Okan found a negative relationship between production and unemployment. Since then, there have been many studies about how unemployment affects production within Okun's law framework; but the results vary in different countries and in different times (boom or recession). Since the results are accompanied with distinct policy implication, a reexamination of this empirical law using a new econometric method seems necessary. This study, using Markov switching approach, examines the validity of Okun's law from the asymmetry perspective across the regimes based on Iran’s data1396: 4 - 1357: 1. The results show that the effect of unemployment on production is asymmetric and nonlinear; so that changes in unemployment do not affect production gap during the boom, but during the recession, positive and negative shocks have a significant effect on the production gap. That is, the reduction in unemployment will more severely affect the production gap in recession.