Investigating the impact of accounting conservatism on the relationship between CEO overconfidence and stock return fluctuations & abnormal stock return in companies listed in the Tehran stock exchange

This study Investigating the impact of accounting conservatism on the relationship between CEO overconfidence and stock return fluctuations & abnormal stock return in companies listed in the Tehran stock exchange. This research is objectively, applicable and through the method of collecting and analyzing in the field of descriptive, correlational. The statistic society population of this research includes the firms listed in the tehran stock exchange as 117 companies operating in various industries over the years 2011 to 2017. To measure CEO overconfidence according to the Ahamad and Duelman (2013) use overinvit index that is related to the investement also to measure stock return fluctuations, the standard deviation of real stock returns has been used for the past 5 years, also to measure abnormal stock return usig the difference between the real return on the share and the market return finally to measure the accounting conservatism used Khan and Wats model. The test assumptions of this study are regular multiple regressions with and using the Eviews software version 9. According to the results of the mentioned test assumptions shows that: accounting conservatism had not a significant impact on the relationship between CEO overconfidence and stock return fluctuations but accounting conservatism had a negative and significant impact on the relationship between CEO overconfidence and abnormal stock return.