Applying the electro method to determine the effects of calendar irregularities in chemical companies listed on the Tehran Stock Exchange

Today, due to the expansion of capital markets, it is essential to identify investor behavior and variables that affect stock prices and returns. The purpose of this study is to use the electrification technique to investigate the effects of irregular calendar day, week and month, with the help of returns and non-systematic risk in chemical companies listed on the Tehran Stock Exchange, in the period 2015-2020. The reason for using the electrification technique, which is a new method in financial research based on stochastic dominance analysis, is the existence of problems in both regression methods with virtual variables and Garch model, as well as achieving more realistic results about the effect of calendar irregularities. The findings show that Monday has the highest and Tuesday the lowest returns for investing in the Tehran Stock Exchange. Also, the best time to invest is from May to the end of summer, especially August, and the most inappropriate time is February and December. In addition, the findings show that investing in the second week of each month is a better opportunity than other weeks.