Iranian Journal of Economic Studies
Volume:3 Issue: 1, Spring 2014

In a structural time series regression model، binary variables have been used to quantify qualitative or categorical quantitative events such as politic and economic structural breaks، regions، age groups and etc. The use of the binary dummy variables is not reasonable because the effect of an event decreases (increases) gradually over time not at once. The simple and basic idea in this paper is to involve a new transition function in a structural time series regression equation model in order to transform the binary dummy variables into a fuzzy set. The main purpose of this paper is to present a new method for endogenous modeling structural breaks in money demand function using fuzzy set. Hence، we model structural breaks in a money demand function via fuzzy set theory، transition functions and binary dummy variables and compare these. After introducing a new transition function، we model money volume shock in 1992 in money demand function. The results indicate that our transition function has better characteristics and accurate results than the binary dummy variable، exponential and logistic transition functions.

This paper studies the effects of the structural variables of the Iranian industries sector on the welfare cost using to the Structure-Conduct-Performance (SCP) theory. In other words، we investigate the role of structural components and their effects on the size of the welfare cost in Iran''s industry sector. We have used the Leibenstein''s model to calculate the deadweight loss and then the panel data model has been used to quantify the model. Leibenstein believed that in many cases the monopolistic industries operate inefficiently due to being on the margin of safety. So in addition to the welfare triangle، the costs of the inefficiency of monopolistic industries should be also considered as the welfare cost. Our results demonstrate that there is a direct relationship between the welfare cost and all of the parameters of the model (barriers to entry، market concentration، economies of scale، state ownership share and firm size).

Laffer curve indicates relationship between tax rate and tax income. The aim of this paper is estimating of laffer curve in Iranian economy. To do so، we have used threshold regression method. Empirical results indicate that since the tax rate is low (the threshold value is less than 0. 0848) in two-regime model، tax rate and tax income have a significant positive relationship، but when the tax rate is high (the threshold value is larger than 0. 0848)، tax rate and tax income have a significant negative relationship.

This paper examines critically the contributions of Cournot، Jevons and Walras as the founders of classical mathematical economics from a methodological standpoint. Advances in different economic schools and doctrines in the 19th century produced an environment of multi-dimensionality in economic analysis which was regarded by the pioneers of classical mathematical economists as a chaotic state. We have demonstrated that the formation of this new discipline، known equivalently as pure or scientific economics، was a response to this so-called chaotic state. We have also shown that the erroneous logic of abstraction in the sense of reducing a multi-dimensional economic system to a one-dimensional mechanical framework as the methodological basis of classical mathematical economics has been the origin of serious shortcomings in mathematical treatment of economics. Based on the writings of Jevons and Walras we have provided evidences to support the claim that advances in Marxian economics can be considered as the prime motive in the development of classical mathematical economics.

This paper tries to analyze the impacts of intermediate goods trade on production، consumption، investment، net exports، employment، labor wage and capital rent of Iran in its bilateral trade relations with China. This analysis has been done by modeling، solving and calibrating an international real business cycles (IRBC) model in period 1980-2009. The results show that when elasticity of substitution between domestic and imported intermediate goods is low، increasing the share of Iran’s imported intermediate goods from China increases volatility of Iran’s macroeconomic variables. The value of an increase in volatility of Iran’s macroeconomic variables depends on elasticity of substitution between domestic and imported intermediate goods، when the elasticity of substitution between domestic and imported intermediate goods is low، an increase in the share of Iran’s imported intermediate goods from China leads to a further increase in the volatility of macroeconomic variables. These results indicate that imports of intermediate goods are an important path through for transmission of shocks between main bilateral trade partners.

This paper estimates the effects of increase in Iran’s non-oil exports on its economic growth as well as sectoral outputs, using a single country, comparative static, exogenous policy Computable General Equilibrium (CGE) model. The paper also investigates the share of tradable sectors in reaching to the targeted growth rate (8%) in 5th socio-economic development plan. For this purpose, the parameters of the model are calibrated based on Iran’s Social Accounting Matrix (SAM) which carries a snapshot of the Iran’s economy. The model is then used to simulate the impact of increasing the exports uniformly across all sectors by 10, 20, and 30 percent on endogenous variables, including sectoral outputs, and GDP. Results suggest that 2.03% of targeted economic growth rate would be achieved by encouraging a 6% growth in exports. Our founding also indicates that industry and mine sector in Iran, would have more influence on growth than other non-oil sectors.