投資人對會計師之信賴程度對更換會計師與審計品質的影響

The Effect of Auditor Credibility on Auditor Change and Audit Quality

有別於過去文獻著重探討更換會計師對審計品質之影響，本研究提出投資人對會計師之信賴程度將會影響公司更換會計師之決策，進而影響審計品質。利用1991 年至2010年臺灣上市上櫃公司之樣本，採用會計師所查核公司之盈餘反應係數，作為投資人對會計師信賴程度之衡量變數，而以財務報表是否重編作為審計品質之衡量變數。研究結果為：（1）當會計師出具對公司不利之審計意見時，公司會提高更換會計師之機率；（2）當投資人對會計師的信賴程度越高，公司因不利審計意見更換會計師之機率越低；（3）當投資人對會計師之信賴程度愈高，公司財務報表重編之機率越低。因此投資人若對會計師越有信心，透過解任壓力之下降，提高之會計師之審計品質，形成正向之自我預期實現。

In contrast to previous studies focusing on discussions of how auditor change affects audit quality, this study proposes that auditor credibility is also a key factor associated with auditor choice and audit quality. We employ auditors’ earnings response coefficients and restatements as proxies for auditor credibility and audit quality, respectively. By using data from the TWSE and the GTSM for the period of 1991 through 2010, we find that firms tend to replace their incumbent auditors when they receive unfavorable opinions. In addition, when auditors issue unfavorable opinions, high-credibility auditors are more likely to be retained than low-credibility auditors. Finally, firms audited by high-credibility auditors are less likely to have financial restatement than firms audited by low-credibility auditors. It implies that when investors have more confidence in auditors, by reducing auditors’ dismissal threats, the audit quality is improved. In other words, investors’ positive expectations make a self-fulfilling prophecy.