Investigating the Relationship between Management Overconfidence, Audit Firm Size, actual earnings management and Auditor's Opinion in Companies Listed in Tehran Stock Exchange

The purpose of this study was to investigate the relationship between managers' Overconfidence, audit firm size, actual earnings management and auditor's comment on Tehran Stock Exchange companies, In such a way that the independent variable managers' overconfidence variable, the size of the moderator variable auditor, the actual earnings management as the mediator variable, and the auditor's opinion variable played the dependent variable. The sample of the study consists of 120 companies listed in Tehran Stock Exchange during the years 2012-2019. Hypotheses were analyzed using multiple linear regression, binary logistic regression and Sobel test that managers' overconfidence had a positive and significant relationship with actual earnings management but a negative and significant relationship with auditor's opinion.  Also, audit firm size as a moderator variable had a significant negative effect on the relationship between management overconfidence and actual earnings management. But actual earnings management did not have a significant effect on the auditor's statement  It also did not mediate the relationship between managers' overconfidence and the auditor's opinion.