فصلنامه پژوهش ها و سیاست های اقتصادی
پیاپی 76 (زمستان 1394)

As technology gap is important in competitiveness , in this study effective factors on technology gap in Iranian manufactures is analyzed from industrial economy’s point of view through panel data with the emphasize on competition degree. The results show that high degree of concentration and profitability encourage the firms to transfer the technology.Also monopoly firms decrease the technology gap through investing on R&D and innovation. Besides, firm entry and business cycles cause technology gap decrease in monopoly manufactures, while import causes the technology gap to increase. In competitive manufactures, firm entry increases the technology gap and the import decreases it.Firm profitability, firm entry ban decrease especially in monopoly manufactures and tariff policy reformation due to their competition degree have a positive role in decreasing technology gap and improving competitiveness.

Today, some economists consider the relation between efficiency and justice when they want to analyze the effects of an economic policy. They interest to know if the two aims are accompanied with each other or not.On the other hand, in utilizing exhaustible resources, including crude oil and natural gas, there are two important questions. First question is about optimal resource extraction and optimal utilizing its revenues. But the second inquires the intergenerational justice or fairness conditions.In this respect, the paper tries to explain the relation between the intergenerational justice policy in utilizing crude oil and natural gas revenues and the welfare level of society over time applying an overlapping generations model for Iran economy.Finally, the model shows that the consumption level of households and also their leisure will be increased if the government respects the intergenerational justice policy and as a result, the welfare level of society will be improved in long run.

In all countries, banks have been played a major role in financing and providing financial services in the economy by granting loans and accepting deposits . Therefore the bank’s efficiency is one of the most important issues in an economy that interests much attention. In some cases , mergers are common methods to increase the efficiency financial institutions and it is one of the ways of restructuring banking and financial institutions as well. The purpose of this paper is to investigate economies of scale after taking place of the merger in Iran. For this purpose, by using data sheets, bank merger of Melat Bank and Tejarat Bank that have the most assets between the Iranian banks has been simulated in duration 1382-1391.By using the Tranclog cost function and SUR method, effect of the economies of scale and closing branches were investigated on reducing costs of banks that were merged hypothetically. The results show that the economies of scale is an important reason of reducing the cost after taking place of the merger but closing branches of target bank post merger will not lead to reduction in costs.

One challenging and critical problem in behavior finance is how to establish verifiable models describing the appearance price bubbles.In this paper, Building on Shleifer and Vishny (1979), seminal work, and with assumption of being myopic arbitragers, the aim is to test if existence of rational bubble is due to activity and response of noise traders to noisy information?Using Tehran Stock Exchange data from 2004:M3 to 2015:M6, an autoregressive regime-switching model of stock price dynamics in which the process creates pricing bubbles in one regime while a linear co-integration relationship between dividends and prices prevails in the other, is estimated. Empirical results indicate that the probability of regime-switching depends on exogenous inflation and lagged price. The results emphasize the importance of the impact of noisy information causing the deviation of prices from intrinsic value.

The political economic relationships atmosphere in recent years, is involved interactions between policy making and economic factors. In this framework, various economic factors influence on decision making and politics formations specially trade policies. In the context of recent studies, this paper by using dynamic panel data and threshold panel data models investigates the effect of business cycles on import protection for selected developing countries during 1995-2011. The results indicate that the effect of cyclical component of GDP on Import protection is negative when the growth rate of cyclical component of GDP is raised. Also the effect of exchange rate and import penetration is negative and significant and the effects of unemployment rate and budget deficit are not significant. Finally, this paper recommends that protective policies should pay more attention to the role of the endogenous factors affecting import protection policies especially economic factors in order to increasing the success of the policies.

This paper is aimed to design a Dynamic Stochastic General Equilibrium in an Islamic framework for Iran. For this purpose an Islamic policy instrument, i.e. The share of government participation in capital funding (MUSHARAKA) is substitute for the interest rate. Then an Islamic policy rule is substitute for Tailor rules in which MUSHARAKA rate will respond to GDP and inflation fluctuations. The results reveal that with the new policy rules, the impact of economic shocks on both GDP and inflation fluctuation will decrease. Then the optimal Islamic(MUSHARAKA) rule is derived. The coefficients of optimal policy rules indicate that monetary authority should respond equally to inflation and the GDP gaps. Therefore, we can conclude that the instrument introduced in this model is quite capable to confront economic fluctuations .So it can be used as an alternative superior instrument for implementing the stabilization policies.

Due to the adverse consequences of inflation in different sectors of the economy, the awareness of the possibility of hyperinflation in the near future makes a great opportunity to avoid the occurrence of hyperinflation. Therefore, this research seeks to design a warning system for hyperinflation. This system using the variables affecting inflation and exploiting the basics of the neural networks appraises the possibility of the occurrence of hyperinflation in the next six months. In this research, from the monthly data of 21 possible variables having effect on inflation from March in 1996 to December in 2011 with the combination of genetics’ algorithm and neural networks the essential variables affected Iran’ inflation are determined. These variables are: Liquidity, government expenditure, labor wage index, interest rates, gross domestic product, Inflation with a lag, and global price index for crude oil. After identifying the fundamental variables using the data related to these variables, the designing of a warning system for inflation is sought. To design such a system, a feed forward neural network with two hidden layers is used. The experimental results of the model indicate the promising performance of the warning system, and the system is able to emit an early warning signal for the occurrence of hyperinflation in near future.

One of the important goals in the developing countries such as Iran is economic growth and development. These countries must consider sufficiently to the foreign trade section. In the recent time the success or failure of the economy of countries strictly depend on the situation of the domestic economy. Because of the interaction with the global economy has become inevitable. According to many survey, state of countries in international economy and trade with the outside world is vital. Since the present study uses panel data model to examine bilateral trade between Iran and partners by Linder theory in period 2006-2010. Linder believe that, the level of per capita income in a country gives a certain pattern of tastes in a country. In fact, the Linder demands overlap model theory estates the bilateral trade between countries with similar per capita income are more than countries with different per capita income. Our results indicate that the negative and significant effect between the volume of trade (exports and imports) and the difference income per capita between the two countries. In the other words more difference country’s per capita income, the volume of trade between the two countries will decrease. The second hypothesis, which suggests a negative relationship between distance and trade volume, in Iran is rejected.

In this paper, we investigate short selling prohibition impacts upon the portfolio optimization using mean variance portfolio theory in Tehran Stock Exchange (TSE). Kuhn-Tucker approach is applied for imposing the non-negativity weight constraints which means no short selling. In other words, we impose the non-negativity constraint deduced from the Kuhn-Tucker approach to simulate the no short selling rule in this market. We also apply conditional estimation of the mean and variance of returns (resulted from GARCH model) along with the simple one to understand the effects of weight estimation. Comparing Sharp ratios, we observed that regardless of the psychological characteristics of the investor, short selling prohibition results in risk-free assetholding and higher return (we will be better off without short selling in this market. Holding the risk-free asset is almost the optimal choice in this case). World experience shows that short selling prohibition does not result in price stability in financial crisis. In other hands, short selling, in its common form, does not seem to be an appropriate tool due to newly founded situation of TSE. Henceforth, stock market development seems to be an appropriate policy and short selling can be used in TSE after being tailored with IRAN’s judicial situation.