Monetary & Financial Economics

Abstract There are various strategies in the field of portfolio formation. In the present study, simple (momentum and inverse) and combined (quantertum and quantrian) approaches have been used to form stock portfolios. The most important factor in the difference between these two types of portfolios is their holding period and ranking. Accordingly, in the present study, after modeling investment strategies, the change in the returns of these strategies over time was examined. Accordingly, the main goal of the present study is to model simple and mixed stock portfolios in different time periods. The present study is applied. The research period is 1390 to 1401. Data from 171 listed companies were used to estimate the model. Nonlinear Bayesian averaging approaches and panel time-varying parameter models were used to model the four stock return strategies. The results indicate that internal factors (within the company) have a positive impact on all four portfolio formation strategies, and external factors (macro factors) have a negative impact on the return of the portfolio composed of the strategies under study. Based on the results, the Quantrian approach provides higher returns for investors compared to other approaches in terms of average short-term, medium-term, and long-term coefficients. Also, based on the results, the momentum approach has been more profitable in the short term and the Quantrian approach in the medium and long term than other strategies.

Abstract A society relies on rational investors to invest because they are the custodians of society's wealth. However, rationality and predictability in decision making is an unattainable idea because decision makers may sometimes act irrationally. Behavioral economics and finance is a result of the achievements of cognitive psychology in the field of human knowledge and the achievements of conventional economics in the field of knowledge of economic phenomena. Despite the distortions and sensory or perceptual errors of man, he is not and will not be able to choose and make decisions completely rationally and with ideal conditions. As a result, it is better to revise the assumptions of the unlimited source of rationality, will and selfishness in economics. The purpose of this article was to examine the role of irregularities in the decision making of investors in the country's capital market. In this study, a foundational data approach and statistical information collected from financial and economic experts in 1402 were used. The results obtained from this study indicated that the role of economic and financial components, market mechanism and executive functions, functions of institutions and financial and accounting components and the index of managerial and legal strategies in irregularities in capital decision making. It was 0.72, 0.55, 0.69 and 0.65 respectively.