---

The optimal usage of oil as a natural resource is an important problem in exporting countries. These countries always are encountered with uncertainty and volatility of oil prices and its effects on real exchange rate. The main purpose of this paper is to investigate the relationship of between oil prices and exchange rate by emphasizing institutional quality in during 1995-2006. The model of this paper is estimated by panel data approach. Findings show that the oil prices have a positive effect on real exchange rate and it reduces international competition power. But institutional quality affects the extent to which the real exchange rates of oil-exporting countries co-move with the oil price. The results show that countries with high institutional quality such as control of corruption and regularity quality have real exchange rates which co-move less with the oil price.

---

Price shocks lead to oil price volatility in world oil markets. In response to this volatility, economic growth may take different regime and behavior patterns in different situation. Investigating this multi behavior patterns can be useful for policymakers to reduce the effect of oil price volatility. In this study, an EGARCH model has developed using the seasonal data of OPEC oil basket nominal prices during 1367:Q1-1389:Q4. Markov switching models is also applied to investigate the multi behavior patterns of economic growth in response to oil price volatility in Iran. The results show that positive oil price shocks sharply lead to formation of oil price volatility, but, the negative price shocks will slightly reduce oil price volatility. Iranian economic growth is affected by this volatility under three different behavior regimes. If the economy switch to one of the regimes (low, medium, high economic growth), the probability of transition between these regimes and their duration is different. So, oil price volatility as a reason for low economic growth in Iran may cause the economy switch to its lower situation.

---

ABSTRACT Considering the major impact which changes in the real exchange rate and crude oil prices have on various sectors of Iran's economy and the importance of the financial markets role in economic growth and development, this paper aimed to investigate the effects of the changes in real exchange rate and crude oil prices on Tehran stock exchange using the Markov-Switching's nonlinear models. To this end, daily data which belonged to the following periods were used: 20:03: 2005 - 13:10:2010 The result of the estimations obtained through the Markov Switching Models indicated that MSIAH model with two regimes out of the various MS model are the most suitable ones. The result of the research showed that the changes in the exogenous variable of real exchange rate and the crude oil price have lagging positive effect on the Stock Exchange Index. Moreover, the effects of these changes with two lagging time intervals are significant and negative. The practical implications of these findings could be beneficial to the investors and policy makers who need to be aware of the exact nature of the effects which changes in the exchange rate and crude oil prices have on the stock exchange index.

---

Abstract

 Forecasting of crude oil price plays a crucial role in optimization of production, marketing and market strategies. Furthermore, it plays a significant role in government’s policies, because the government sets and implements its policies not only according to the current situation but also according to short run and long run predictions of important economic variables like oil price. The main purpose of this study is modeling and forecasting spot oil price of Iran by using GARCH model and A Gravitational Search Algorithm. Performed forecasts of this study are based in static and out-of-sample forecasting and each subseries data is divided in to two parts: data for estimation and data for forecasting. The forecast horizon is next leading period and its length is one month. In this study the selected models for forecasting spot oil of Iran are GARCH(2,1) and a Cobb Douglas function which is functional of prices of 5 days ago. Finally, the performances of these models are compared. For comparison of these models MSE, RMSE, MAE, and MAPE criteria are used and the results indicate that except in MAPE criterion, the mentioned criteria are smaller for GARCH model in comparison to GSA algorithm.

---

The fluctuations in the oil price with uncertainty, as an exogenous variable, is the most important factor affecting the fluctuations in the GDP of the countries especially OPEC. This study examines the effect of oil price uncertainty on the Iran’s GDP growth using the seasonal data for the period 1988(1)-2011(4). The model used in this study is the asymmetric VARMA, MVGARCH-M and the estimated method is quasi maximum likelihood (QML). The results indicated that there is a negative and significant relationship between oil price and economic growth over the period. Furthermore, the results show that the conditional variance-covariance process underlying output growth and change in oil price exhibits non-diagonality and asymmetry.