فصلنامه تحقیقات اقتصادی
پیاپی 94 (بهار 1390)

In this paper, we have studied the effect of population on Iranian economic growth by using optimal growth theory. Optimal growth theory is a nonlinear dynamic planning. Classical approaches in mathematics are used for solving these nonlinear systems. But, in this study, we have used Genetic Algorithm (GA) method. As results show, it seems that population growth in previous years (1350- 1386), can describe an important part of growth rate for per capita capital and per capita output in Iranian economy. Annaual growth rate of 2.5% in Iran population during 1350-86, has increased per capita consumption, per capita income, per capita saving and per capita capital formation by 14%, 14%, 8% and 46% respectively. Results of the study also suggest that it is better to have a positive growth rate for Iranian future population rather than a zero rate, because with a growing population we will have a higher rate for capital formation and per capita output. Moreover, if policy makers could move the system to a more equated situation (inter-temporal equity) we could have the more positive effect of population growth on the level of economic activities. If population grows by 1%, per capita output and per capita capital formation will be growth 8.2% and 18 % respectively.

The ongoing study aims at a brief pathology on saving in Iran's private sector. The factors effect on saving in private sector have been introduced, including oil revenues, real interest rate of banking long-term deposits, ratio of stocks transactions value to Gross National Production (GNP), proportion of employed population to total population, Inflation rate and Gini coefficient during 1974-2007 term. Then, we tested the hypotheses by using model of the least-squares method. At last, after elimination some of insignificance variables, the presence of positive effects in oil revenues growth and the ratio of the employed people to total population, and the negative influence of increase in banking long- term deposit's real interest rate on saving through private sector were verified. With respect to classic models in which interest rate positively affect on saving, it was verified in the current study that there was a negative relationship between real interest rate of banking long-term deposits and saving in private sector so it requires note that Iran's special economic conditions and the existing high inflation which are higher than banking deposits rate for the most occasions, led banking real interest to be negative and reject of Classics Theory in Iran.

The purpose of this research is investigation of application of the arbitrage pricing theory and effect of unanticipated changes in a set of macroeconomic variables such as inflation rate, money supply, exchange rate, oil price, term structure and industrial production on expected security return in Tehran stock exchange. In this research, data are analyzed quarterly for the period of 1997-2008 (44 quarter) and by using of the system of iterated non-linear seemingly unrelated regressions. The results indicate that risk premium associated with unanticipated changes of variables of money supply, exchange rate, term structure and industrial production are significant at the 5% level and the restrictions of the APT reveals on an unrestricted linear factor model. Therefore, the arbitrage pricing theory is a reasonable model for explanation of expected security return and the significant macroeconomic variables are sources of systematic risk in Tehran stock exchange.

This study tries to measure core inflation in Iran's economy, using SVAR method, spanning the period 1973-2007. The necessity of knowing about core inflation is that it increases signals to likely noises (shocks). Through using coring inflation criteria in policy making, monetary policies become more effective, as policymakers just react to fluctuations in measured inflation, ignoring temporary noises. Core inflation criteria is an appropriate index for both the measurement of current and future inflation trends, and an applicable target for monetary policy. In this study, core inflation is considered as "a component of measured inflation with no effect on real output either in the long run or short run". In an attempt to measure core inflation in Iran, three variables as oil price, gross national product, and consumer price index are deployed in a Structural Vector Auto Regressive (SVAR) model, imposing some restrictions to make the model compliant with the structure of Iran's economy. The results show that in most cases, headline inflationary pressures have been more than measured inflation, for there have been deflationary pressures of oil export revenues in the economy.

The quality of firms’ reaction against demand uncertainty affects the production inputs employment. In this research I have studied and compared the behavior of active firms in manufacturing sector with respect to the risk attitude and tested it’s effect on production inputs combination(with the special emphasize on labor employment). The research findings reveal that active firms in manufacturing of food, beverage and tobacco products (code31), manufacturing of textile, wearing apparel and leather products (code32) and manufacturing of wood and products of wood (code33) don’t significantly react against the risk resulted from demand uncertainty so demand uncertainty has not significant effect on capital-labor ratio. In manufacturing of paper, publishing and printing (code34), due to the risk averseness of the firms demand uncertainty increases the capital-labor ratio. In manufacturing of chemical products (code35), manufacturing of non-metallic mineral products (code36), manufacturing of basic metal (code37) and manufacturing of machinery, equipment and metal instruments products (code38), however, firms negatively react against the demand uncertainty and rise in demand uncertainty decreases the labor intensity in these sub- sectors.

This paper examines the impact of 2005 presidential election of Iran on the Tehran stock exchange volatility as a political shock. It uses GARCH family (FIEGARCH, EGARCH, and GARCH) and Markov Regime Switching (MRS) models as the analytical frameworks for the main the stock daily prices index. Our findings confirm statistical validity of ARIMA – FIEGARCH-X and AR(1) MRS as appropriate specifications. Furthermore, uncertainty in the market caused more volatility before the election and this volatility has continued after the election. Consequently, if the right party wins the election, the market volatility increases and it is actually what investors expect. In addition, MRS reveals that probability of staying in a high volatile situation on average is 0. 71 and the volatility duration in the market is 4 days.

After establishment of the World Trade Organization (WTO) in 1995, not only all countries around the world had to receive progressively the WTO accession but also those that had higher economic potentials benefited further advantages from their memberships. One goal which has been followed by the WTO has relied on economic convergence. It is now a time to ask whether convergence in monetary policy, interest rate and exchange rate expands trade relations between the WTO members and between members of other economics unions such as EU, ASEAN and NAFTA. The purpose of this paper is to find out an empirical answer through analyzing relationship between economic convergence and international trade flows. To this end, we examine such effects on trade by specifying a panel econometric model using data of 126 countries worldwide during the period 1995-2004. The empirical results emphasize the role of global financial convergence on expanding trade relations between members of the WTO and other selected unions.

The environmental degradation increase during recent years, has proposed the investigation of economic activities and environmental indicators relation. Mostly a unidirectional causality from economic activities to pollution is assumed. While the direction of causality between pollution and economic growth has specific policy implications, presumption of this direction may influence the nature of the relationship. Therefore, the examination of economic dimensions of pollutant emissions and its consequents has significant importance. This study examines the long-run relationship between emissions and economic growth considering fossil fuel consumption and openness variables in Iran during 1961-2006. Using causality test based on error correction mechanism shows that there exists causality from economic growth, energy consumption and openness to carbon emission, but it is not hold vice versa. On one hand fossil fuel consumptions has no effect on the economic growth and on the other it is the cause of pollutant emissions. So as a policy implication, fossil fuel conservation can be as a way to reduce pollutions.

Economic Development Plans normally contain some policy objectives, especially for the most important macroeconomic variables. Governments are expected to take best policies to achieve these objectives, although due to some structural or other impediments they may fail to touch the objectives. We have attempted to uncover the determinants of private consumption and investment as the objectives of the economic plan, via estimating a very simple model and then determine the government's best policy options in achieving the objectives or in a more precise words, determining best policy options for minimizing the deviations from the targets of the Fourth Five Year Development Plan, making use of an Optimal Control Theory method. Accordingly, we employed a deterministic class Quadratic Linear Tracking Problem to obtain the optimal trajectories for objective and policy/control variables. In addition to the private consumption and investment which were determined as objective variables, government expenditures and money stock were considered as control/policy variables representing fiscal and monetary policy, respectively. The results of the study revealed that due to the Crowding-out Effect between government Expenditures and Private Investment during the period (1368-1383), which is considered a structural problem, the policymakers loose fiscal policy instrument in order to ascertain the objectives. Instead, they have to rely on the monetary policy instrument which may in turn cause inflation and make the economic plan deviate from its inflation targets.

The protection of households against catastrophic medical payment always has been one of the most important objectives in any health care system. This study assessed the performance of Iranian health insurance schemes in protection the patients against catastrophic medical payment. This is an analytical study which performed in a cross sectional design on 400 patients that hospitalized in selected hospitals affiliated to Iran University of Medical Science. Among 16 variables only 8 variables include: Household’s head gender, Number of hospitalization, Residency in Tehran, Income level, other family member’s illness, Ownership of house, Number of household’s members and finally the coverage of complementary health insurance have had significant relation with the probability of catastrophic medical payment occurrence. It seems that policy makers should pay more attention to socio-economic factors, demographic factors and the epidemiology of diseases in our country to design suitable prepayment schemes.