Prior studies that examine audit quality and earnings management mostly separate discretionary accruals from total accruals and use discretionary accruals (or absolute value of discretionary accruals) to measure the magnitude of earnings management. Although most of those studies find audit quality is able to restrain the degree of earnings manipulation, few evaluate whether audit quality is capable of reducing the information risk faced by investors. Compared to discretionary accruals, accruals quality measured by the extent to which current accruals map into operating cash flow realization is more directly related to information risk. The purpose of this study is to examine the association between audit quality and information risk faced by investors, using accruals quality to proxy for information risk and adopting auditor brand name, audit-firm tenure, CPA tenure and auditor industry specialization as measures of audit quality. The study hypothesizes that auditor brand name, audit-firm tenure, CPA tenure and auditor industry specialization will contribute positively to reduce information risk faced by investors. The empirical results indicate (1) higher quality auditors (Big 4 auditors) are able to lower the information risk faced by investors, (2) the longer the audit-firm tenure, the lower the information risk faced by investors, (3) clients of industry specialist auditors have lower information risk than clients of non-specialist auditors, and (4) the relationship between audit-partner tenure and information risk is yet insignificant. Finally, the results further show that the divergence between control rights and cash flow rights will weaken the negative relationship between auditor brand name and information risk as well as the negative relationship between audit-firm tenure and information risk. However, it does not affect the negative relationship between auditor industry specialization and information risk; it may be because the industry specialist auditors can better resist the pressure from the controlling shareholders that can help alleviate the information risk faced by investors.

近來陸續爆出的舞弊案件已連帶引起了社會大眾對關係人交易行為的注意。本文先探討審計品質與關係人交易之關聯性，而實證結果顯示關係人銷貨、進貨、應收款項與應付款項交易與審計品質皆呈負向關係，足見關係人交易之查核是困難的。因此本文期望透過外部審計人員的專業屬性來降低關係人交易對審計品質產生的不良影響，提升投資人對公司財務報導的信任。過去文獻針對會計師專業屬性部分，指出會計師事務所規模愈大以及產業專精程度愈高者，具備較佳的查核品質。研究結果顯示當關係人銷貨、進貨及應收款項交易係由四大會計師事務所或產業專家會計師事務所查核時，因大型會計師事務所或產業專家會計師事務所具備較佳會計師專業屬性，能抑制或減少關係人交易對審計品質之負面影響，而提升財務報表之審計品質。 / Numerous financial reporting frauds over recent years have made related party transactions the center of public attention. We first investigate the association between related party transactions and audit quality (proxied by discretionary accruals), and find that four kinds of related party transactions (including sales to related parties, purchases from related parties, accounts receivable from related parties and payable to related parties) all have negative impacts on audit quality. We posit that (1) external auditing is a monitoring mechanism to reduce audit quality decline caused by related party transactions, and (2) auditor attributes including big 4 audit firms and industry specialist audit firms can mitigate the audit quality decline thereof. Empirical results show that companies audited by big 4 or industry specialist audit firms, whose sales to related parties, purchases from related parties and accounts receivable from related parties show significantly smaller negative impacts on audit quality than companies not audited by big 4 or industry specialist audit firms.

本文旨在探討關鍵查核事項與會計師事務所特性之關聯性。其中，會計師事務所特性係指其獨立性與專業能力，並分別以任期與產業專家衡量之。 　　本文實證研究結果如下：其一，主查會計師之任期對關鍵查核事項幾無影響。其二，產業專家會計師事務所與關鍵查核事項之數量及品質僅有部分試驗呈正相關。其三，產業專家主查會計師其對關鍵查核事項之數量及品質均有正面影響。 　　在增額測試的部分，結果如下：其一，對產業專家主查會計師而言，任期對關鍵查核事項有正面效果。其二，會計師事務所與主查會計師俱為產業專家的會計師對關鍵查核事項之正面影響力大於僅有會計師事務所為產業專家的會計師。最後，會計師的專業能力使其更有能力以簡明扼要的文字呈現關鍵查核事項。 / The objective of this thesis is to investigate the relationship between key audit matters (KAMs) and audit firm characteristics. In this study, audit firm characteristics are focused on their independence and ability, and are measured by tenure and industry expertise, respectively. The empirical results can be summarized as follows. Firstly, lead partners tenure has little effect on KAMs. Secondly, partial evidence is found on the association between firm-level industry specialist auditors and KAMs. Thirdly, partner-level industry specialist auditors have positive effects on both the quantity and quality of KAMs. In further examinations, the results are as follows. Firstly, tenure has positive effects on KAMs when the auditors are partner-level industry specialist. Secondly, industry experts at both firm- and partner-levels have stronger positive effects on KAMs then industry experts at firm-level alone. Lastly, auditors’ capacity allows them to present KAMs more concisely.