Department of Industrial Engineering and Management, Shahrood University of Technology, Semnan, Iran.
n this paper, trading symbols of the 30 largest companies listed in the Tehran Stock Exchange (TSE) were ranked based on the asymmetry information risk. Using the Ersan and Alici (2016) modified clustering algorithm (EA), we estimated the probability of informed trading (PIN) to measure the asymmetry information among traders for each trading symbol and trading day through two-year horizon from 20th March 2015 to 19th March 2017. Furthermore, we used the analysis of variance (ANOVA) method to determine the source of variation in the estimated PIN. The results showed that the estimated PIN is less than 0.1 for the 88.2% of the firms-trading days and that is equal to zero for the 60% of the firms-trading days. Symbol trade “MAPN” is traded with the status of full asymmetric information in about 75% of its trading days. Factor weekdays have no significant effect on changing the PIN index. The annual average of the estimated PIN index for the first year is significantly less than the second year. The effects of firm specification on the PIN value will be disappeared after one year.