本文旨在驗證台灣資本市場中公司自願性盈餘預測品質與會計師提供非審計服務的關係。不同於美國或其它先進國家的市場，在台灣上市公司進行盈餘預測時需要會計師複核並提出審計意見。基本上，會計師進行複核程序(review)所提供的確信程度相較於審計程序(audit)較低。因此本文使用台灣上市公司的資料進行實證研究，結果顯示當公司有較高的非審計服務費用 (NAS)，較會發佈樂觀與不正確的盈餘預測。我們的結果提供了非審計服務可能會影響會計師獨立性的證據。此外，我們也發現在盈餘預測宣告日，會計師提供給客戶的非審計服務(NAS)與市場報酬呈顯著負向關係，結果指出非審計服務加重了會計師對客戶的經濟依賴(economic dependence)和投資人的價格反應。 This paper examines the association between the quality of voluntary earnings forecasts, as measured by forecast bias and accuracy reviewed by an incumbent CPAs, and the purchase of non-audit services (NAS) from the incumbent auditor. In the context of this study, we focus primarily on the Taiwanese market. Unlike in the U.K. and U.S, management forecasts must be reviewed by the incumbent CPA in Taiwan. Besides, enforcement of rules with regard to the provision of review-level assurance for management earnings forecasts tends to be less stringent than one of audit-level assurance for financial reporting. Using panel data of audit and non-audit fees available for Taiwanese firms, we find that firms with a high ratio of NAS tend to issue more optimistically biased and inaccurate forecasts under a lower auditor liability regime. These results provide some support for concerns expressed about the potential impact of unusually high levels of NAS on auditor independence and ultimately, the quality of audited financial reports. We also find that the NAS is negatively associated with stock returns on the date of announcements of voluntary earnings forecasts. These results are consistent with arguments that the provision of non-audit services strengthens an auditor’s economic bond with the client and that investors price this effect.
