Document Type : Research Paper



Portfolio selection problem is an important field of capital assignment and budgeting in managerial finance and had proposed patterns for optimal selection of portfolio from the past. For this purpose we suggest a fuzzy ranking method with mathematical approach. This research is a survey in Tehran stock exchange. Statistical population inclusive 50 superior companies of Tehran stock exchange in 1387. By survey of financial data of these companies, 20 companies have selected and weekly returns in 1387 have been calculated for them. In first stage, 20,000 random portfolios have been generated by a computer program. Each of these portfolios is composed of 20 companies that quantity of investment in each of them are between 0% and 100% and selected randomly. The uncertainty on the returns of each portfolio is approximated by means of a trapezoidal fuzzy number. A rank index that accounts for both expected return and risk is defined, allowing the decision-maker to compare different portfolios and select best portfolio. Conclusions showed that, according to risk aversion of investor, several optimal portfolios can be selected. In this article we suggested 3 optimal portfolios.