Differential effects of market concentration on oligopolistic and atomistic segments: Evidence of audit fees, audit quality, and auditor switch and the effect of real activities management on audit report lags, accrual management, and audit fees

In the first essay, I divide the local audit market into the oligopolistic segment and atomistic segment and examine whether the differential effect of audit market concentration on audit fees, audit quality, and auditor switch in these two segments. I find that the market concentration raises the audit fees, but lowers the audit quality in the oligopolistic segment. In contrast, the market concentration lowers audit fees, but raises the audit quality in the atomistic segment. Moreover, I find that market concentration reduces the probability of auditor switch in both oligopolistic and atomistic segments. My findings reveal that audit market concentration only reduces the competition among oligopolistic segment. In contrast, the atomistic segment becomes more compressed and more competitive in a highly concentrated market. I also examine the nonlinear association between the auditor's market share and audit quality. I find that the relation between the market share and audit quality is an inverted U-curve.;The second essay examines (1) the effect of real activities manipulation (RAM) on the audit report lags, (2) the impact of RAM on the audit fee and audit quality of industry experts, and (3) the linkages between accrual-based earnings management (AM), RAM, and audit fees. I find that RAM is associated with longer audit report lags. I also find that industry specialist auditor charge higher audit fees and make a more constraining influence on AM when their clients engage in aggressive RAM. However, I do not find that RAM affects the association between AM and audit fees.