沙賓法案後異常審計公費與審計品質之關聯性研究

Abstract

在沙賓法案實施後，審計委員會負責公司之聘請外部審計機構，決定審計公費以及監督查核工作等，因此會計師與客戶之間的經濟依賴可能被降低。另一方面，由於客戶之議價能力較高讓審計公費低於預期，會計師可能減少查核工作而造成較差的審計品質。本研究以2005至2011年間於NYSE及NASDAQ的上市公司為樣本，且將異常審計公費分為過高及過低兩部份，作為衝量經濟依賴及客戶的議價能力，而審計品質即以裁決性應計項目作為衡量方法。 本研究結果顯示：過高的異常審計公費對裁決性應計項目的關聯並不顯著，相反，過低的異常審計公費對裁決性應計項目的影響為正相關。此外，對非四大事務所來說，異常審計公費與審計品質並沒有顯著關聯。因此，本研究認為，於沙賓法案落實後，或許因審計委員會負責公司之聘請外部會計師，降低客戶與會計師之間的經濟依賴。但是，過低的審計費用卻有可能使審計品質下降，而此關係只局限於四大事務所。

This study re-examines the relationship between abnormal audit fees and audit quality in the period after the Sarbanes-Oxley Act of 2002 (SOX). After SOX, the audit committee will now be responsible for appointing auditors, approving the compensations and overseeing the audit work. This effectively mitigates the economic bonding between auditors and clients. Also, clients with stronger bargaining power may instead experience a decrease in audit quality, as lower audit fees may mean less effort from auditors. This study divides abnormal audit fees into positive and negative to measure economic bonding and bargaining power, respectively. Examining firms listed in NYSE and NASDAQ from 2005-2011, the results reveal that audit quality, using absolute discretionary accruals as proxy, has no association with positive abnormal audit fees. This is in contrast with the expectation that higher audit fees should result in better audit quality. On the other hand, higher negative abnormal audit fees leads to lower audit quality, which is consistent with expectations. Also, this paper partitions the sample data into Big N and non-Big N subsamples, with Big N auditors less likely to reduce audit quality if lower audit fees are received.