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The ability of OLG models in analyzing and simulating the various fields of an economy, such as the investigation of endogenous growth policies, the development of intergenerational equity criteria and the reform of social security system, has caused these models to have a special position among economists in recent decades. However, difficulties in quantifying these models and analyzing their stability properties have led them to remain only theoretical and receiving less attention from empirical viewpoints. This paper uses the proposed method by Auerbach and Kotlikoff to estimate a 55-period overlapping generations model. Then due to failures of the Iran’s Pension System, it analyses and simulates Pension System within overlapping generation’s model with heterogeneous agents living in 55 periods. Thus we study the effects of transition from the Pay-As-You-Go Pension to the Fully Funded Pension System in the process of capital accumulation, national production and national consumption. The findings indicate that the individual optimal consumption-saving behavior varies under different social security systems. The results of the simulation model show that in addition to increasing the personal financial assets, Fully Funded Pension System provides a higher physical capital accumulation for the economy than that of ‌Pay-as-you-go Pension System. In addition to higher levels of national consumption and production, the transition to the new system causes people to have more incentive to stay in the labor market and to complete their career because they have higher labor income than the old pension system.

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One of the important targets of the economic planning is economic growth via enhancement of the labor productivity. In this regard, education expenditures play a crucial role. This study aims at investigating the effect of education expenditures on the level of human capital and economic growth through a computable general equilibrium approach. The data on economic variables and social accounting matrix belongs to the year 2001. Three scenarios on education expenditures are defined and their effect on human capital and economic growth are estimated. The results show that education expenditures have positive effects on economic growth and human capital. A 50% increase in education expenditures in the first period causes 3.81 and 5.8 percent increase in human capital and economic growth respectively. In the second period, the same increase in education expenditures affects human capital and economic growth positively by 5.4 and 7.3 percent respectively. Although separating the economic growth into human and physical factors in the first period shows that there is no relationship between human capital and economic growth, but in second period this separation causes a relationship between the two factors.

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Changes infertility ratesasone of the factors affecting the demographic changes and its rolein the labor supply and there fore economic growth, as an important element ofsocio-economic development of every country is considered. So that the importance of demographic changes in each country in recent years has increased resulting aging population in general and specifically decreased fertility that increased concerns for the global economy and the majority of developing countries-including Iran. However, the range of empirical studies in incurred countries is very limited and in most studies, the surface shape of the subject has investigated in a simple line a reconometric model. Thus this study investigates the impact of fertility’s changes one conomic well-being in selected MENAcountries over the 1970-2010. We apply dynamic consumer optimization model that incorporates end ogenous fertility as well as end ogenous education and health investments offered by Prettner and et al. (2013). The estimation results of non-linear panel smooth transition regression model reports the negative effect of fertility and positive effect of revenue and population on effective labor force, which show that the quantity-quality trade off in population acts in favor of labor force and increases its quality and causes output growth and well-being. This issue is in ferable from positive effect of population on education and health-as delineator indices for well-being- in the countries under investigation.