“…However, a variety of definitions are used to proxy for audit quality in the literature. Due to the inability of directly observing audit quality, several observable factors are used as a surrogate, including the size of audit firms (DeAngelo, 1981;Palmrose, 1988), tenure on audit engagement (Simunic & Stein, 1987), audit structure (Knapp, 1991), litigations or SEC actions against listed firms and their auditors (Allen, Linville, & Scott, 2005), and auditors' industrial expertise composition (Schauer, 2002). A high-quality auditor should have independence (relationship based), sufficient expertise (technique based), and high integrity (honesty and forthrightness).…”