the relationship between audit tenure and audit opinion in tehran stock exchange

the major goal of the present research is to study the relationship between audit tenure and audit opinion in firms enlisted in tehran stock exchange. the statistical population for the present study includes all firms in tehran stock exchange enlisted during the years between 2008 and 2014 and the sample comprised of 111 firms after using screening method and the deletion of incomplete observations. in this research audit tenure has been considered as independent variable to investigate about its effect on audit report types including accepted reports, conditioned reports, lack of opinion reports, and rejected reports. this research is applied regarding the goal and is descriptive-correlation type regarding the nature and content and also it is post incidental (quasi-experimental). it means that it has been done based on analyzing past and historical data (firms' financial statements). in this study panel data with fixed effects have been utilized. the results of analyzing firms' data by using multiple variable regression in an assurance level of %95 show that there has been a direct relationship between audit tenure and accepted reports and there has been a reverse relationship between audit tenure and conditioned reports and lack of opinion reports. also these results showed that there has not been a meaningful relationship between audit tenure and rejected reports.