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Iran plans to export natural gas (NG) to Western Europe using a system of pipelines running through Iran, Turkey, and Western Europe. International gas pricing is usually undertaken through negotiations between buyers and sellers on a bilateral basis. Currently, Russia is the only exporter of gas from the Former Soviet region. So, Russia competes strongly with Iran to export NG to Western Europe. This paper develops a bargaining model to study natural gas pricing and analyze competition between Iran and Russia as gas suppliers to Western Europe. In this model, it is assumed that NG pricing is usually linked to the prices of alternative fuels as competing energy sources. Therefore, in light of previous evidence, it is reasonable to consider that there is a long-run relationship between NG price and price of alternative fuels. Initially, a regression model is specified to investigate unlagged relationship among variables. This relationship is estimated using the Johansen cointegration technique and then we forecast margins of the Iranian NG price. Finally, a VECM model is identified and used to forecast the lower and upper bounds of future NG price.

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Since various economic sectors, in particular housing sector, need to bank loans, the variations in lending behavior of banks due to changes in key economic variables may jeopardize the sound economic activities. In this study the lending behavior of Bank Maskan of Iran was modeled by a Vector Auto-regression (VAR) model during 1991-2011. The results of long run Vector Error Correction Model (VECM) indicated that the broad money supply, inflation rate and stock price fluctuations have indirect effects on lending behavior of Bank Maskan, however the effect of exchange rate variations is positive. In addition, the results of short run VECM showed that variations in the broad money supply have direct effects on lending behavior of Bank Maskan, but inflation rate, exchange rate and stock price fluctuations have no significant effects.

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Trade balance is regarded as both main macroeconomic factor and strategic constraint in developing countries. Exchange rate, which is defined as parity relationship between national currency and foreign currencies, is a vital determinant of countries’ trade balance. As the real effective exchange rate measures the changes in prices and relative costs by a common currency, it is the most popular indicator to measure competitiveness. On one hand, fluctuation of this index represents disequilibrium in the economy, and on the other hand, it is the cause of more instability. Since the direction and size of the effects of real exchange rate on trade balance is an important macroeconomic issue, this articleinvestigates the real effective exchange rate changes on trade balance in Iran and its’ major partners using the Vector Error Correction Model ( VECM ) over the period 1993-2011. The results indicate that the real effective exchange rate volatility reduces trade balance only for Germany in the short run and rises it for Italy in the long run.

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Among the food products, grains play an important role in the consumption patterns of people, especially in the developing countries. Since Iran's main source of public dietary energy comes directly from grains, investigating and identifying the determinants of import of these products can be an important step towards food security. Most experimental studies consider import of grains as only a function of relative prices and real income, whereas, income inequality is also a variable affecting the import of grains. The present study evaluates the effect of income inequality on the import of grains in Iran's economy during the years 1969-2009. For this purpose, the relationship of grain import with gross domestic production (GDP), grain production, real exchange rate, and income inequality was evaluated for Iran by using the Vector Error Correction Model (VECM). The results indicate that the relationship between income inequality and grain import is positive and its coefficient is +0.55%. This implies that 1% increase in income inequality increases grain import by 0.55%. Also, the effect of gross domestic production on grains import is positive and the real exchange rate and grains production variables have a negative and significant effect on grains import.