Economics Research

Abstract This paper seeks to address the question that whether and to what extent does Social Security retirement benefits cause early retirement. ‎This question is studied under “Option Value” and “Peak Value” models, in which the individual's retirement decision is derived as a function of future variations of present value of social security wealth. The‎ results indicate that Social Security (in the form of retirement benefits) has a significant effect on retirement ‎decisions‎ and that the future path of these benefits is an important determinant of the probability of retirement among would-be retired men.

Abstract Economic agents are constantly making decisions to maximize their expected utilities while accepting some risks. The question is that, how the efficient portfolio of the assets in a specific level of risk is formed to maximize the individual’s utility?             To model the behavior of decision maker, economists and financial mathematicians consider both the variables which affect individual’s decision making behaviour, and the methods to include real world uncertainties. In the model presented in this paper the decision maker chooses between two types of assets: risky and risk-free. The returns on these two types are different and the utility of the decision maker is a function of his wealth (consisting of his initial wealth and the returns of his portfolio of the assets). The comparison between the results of financial modeling with decision-making theories under uncertainty within microeconomic literature reveals the impacts of three factors: degree of risk-aversion, relative return of assets and volatility of risky assets prices, on optimum portfolio allocation.