Investigating the effect of companies' political relations with the government and information asymmetry on short-term and long-term stock price volatility after initial public offering

Given the importance of stock price fluctuations after the initial public offering for investors,the important factors that cause these fluctuations were examined. For this purpose, the political relations of companies with the government(using the methods of company size factors and the percentage of government ownership)and information asymmetry(using the difference in the offer and sale price range)were investigated that To examine the relationship between political communication and stock price volatility by comparing the means of two independent groups and Multivariate regression method was used to investigate the relationship of information asymmetry.Also,to examine the more accurate dimensions of this relationship, to examine the control variables of supplier reputation and credibilit(using three registered capital characteristics relative market share of initial supply and Number of managed initial public offerings)institutional ownership,earnings management, audit quality and number of shareholders.Findings show that companies'political relations with the government do not affect short-term stock price fluctuations,but these fluctuations in the long run are less for companies with political relations with the governmen (company size factors)than companies without connections. It is political Also, increasing information asymmetry increases stock price volatility after initial public offerings in the long run, but is not effective in the short run.Also, the reputation and credibility of the supplier does not affect price fluctuations, which indicates the lack of attention of investors in Iran at the time of initial public offering to the reputation and credibility of the supplier and the reputation and credibility of the supplier can not affect investors'decisions unlike research in other countries.