Effect of ownership Concentration and Size on Conditional Conservatism and Audit Fees relationships

The main propose of this research is the analyses of effect of Ownership concentration and firm size on the relationship between conditional conservatism and audit fees. In this study, the effect of conditional conservatism based on three models of a) Basu (1997) Profit and returns standard regression, b) the accruals–cash flows–based model, and c) the earnings persistence model for the 109 companies listed on the tehran Stock Exchange, between the years 2010-2017, which were selected by random removal method, Has been investigated. The results based on fixed effects model and multiple regression method show that the Conditional conservatism (only based on the Basu (1997) standard regression and earnings persistence), in large companies are significant effect on audit fees and in small companies do not have significant effect on audit fees. And the interaction between ownership concentration and conditional conservatism index only based on earnings persistence and Profit and returns models are significant effect (Positive and Negative Respectively) on audit fees.