自2005年開始PCAOB對外國之註冊會計師事務所進行國際檢查，至今已逾十年，然而制度實施之初面臨許多質疑。而今，已有文獻指出不論是美國或是其他國家，PCAOB的檢查皆具有一定效益，且具有外溢效果。惟各國間的國家特性因素於目前文獻中尚有發展空間，因此本研究欲了解國家特性是否會影響PCAOB國際檢查的外溢效果。 　　本研究以2004年至2013年間35國的資料計算裁決性應計數，以此代理審計品質，觀察各國審計品質於檢查前後的變化，並以法規執行力以及四大會計師事務所市占率代理國家特性，進一步了解不同特性的國家，其審計品質改變幅度的差異。 　　根據實證結果發現，當一國的法規執行力較高或是四大會計師事務所市占率較高時，審計品質較佳，因此於PCAOB國際檢查後審計品質提升幅度較小。各國的準則制定機構可透過本研究的國家分類，量身訂定更符合國家的準則，以改善審計品質。 / Since 2005, PCAOB has inspected foreign registered audit firms for a period over ten years. The benefits of inspection in both the United States and other countries are documented by extant literature, but the research of country characteristics on the spillover benefits is still lacking. In this study, we document how country characteristics influence the spillover effect of PCAOB international inspection on audit quality. This study uses discretionary accruals as the proxy of audit quality. Our data of non-US-listed companies from 35 countries during 2004-2013 are taken from Datastream. In addition, we use legal enforcement and Big 4 dominance to investigate how country characteristics affect the magnitude of audit quality changes. According to empirical results, we find that countries with higher legal enforcement or Big 4 dominance provide better audit quality. Therefore, PCAOB international inspections in these countries generate smaller magnitude of audit quality improvement than in countries with lower legal enforcement and Big 4 dominance . Our results suggest that regulators of different countries should develop more tailored regulation in order to improve audit quality of their respective countries.

本研究以我國1994年至2003年由四大會計師事務所查核簽證之上市上櫃公司為研究對象，探討會計師之產業專精與任期及其交互作用對於查核品質之影響，其中以裁決性應計數作為查核品質之代理變數，並同時採用會計師事務所及合夥會計師在特定產業之市場佔有率，作為產業專家之衡量指標。實證結果發現，產業專家可以限制受查客戶透過裁決性應計數從事盈餘管理，而以合夥會計師為基礎所計算之市場佔有率較會計師事務所為基礎所計算之市場佔有率，更能解釋審計品質的差異。在任期方面，研究結果顯示，會計師任期愈長愈能限制盈餘管理，而任期對於裁決性應計數絕對値之影響係反映於任期較長會計師之查核年資。但進一步檢測會計師對管理當局操弄盈餘向上或向下的態度是否隨著任期之增長而有所不同時，本研究發現，當管理當局操弄盈餘使其降低時，會計師任期增長愈能抑制管理當局向下操弄盈餘以預留未來盈餘空間；而在管理當局操弄盈餘使其增加時，會計師任期增長則沒有理由支持具查核品質。此外，在產業專家與任期之交互作用對查核品質影響方面，實證結果發現，產業專家會計師抑制盈餘管理的能力較非產業專家好，所以較不須要透過任期的增加來提升其偵測盈餘管理的能力。 / This study uses the sample comprised of listed and OTC firms in Taiwan during 1994-2003 and examines the effects of auditor industry specialization, auditor tenure and the interaction on audit quality. I use discretionary accruals as proxies for audit quality and industry specialization is measured in terms of both audit firm market share in an industry and auditor market share in an industry. My empirical results provide evidence that industry specialist auditors can restrict accruals-based earnings management and explain the differentiation of audit quality more than industry specialist audit firms. About auditor tenure, I find that absolute discretionary accruals decline with auditor tenure and tenure traced at the longer auditor tenure is superior to shorter auditor tenure. The results show that longer auditor tenure enhances audit quality. In addition, a further analysis shows that the clients have motivations on income-decreasing earnings management, auditors can limit management’s ability to create reserve to manage future earnings. But the clients have motivations on income-increasing earnings management, the study did not provide sufficient evidences to explain that audit quality is improved with tenure. Besides, the result of empirical analysis support my estimation about the interaction between auditor industry specialization and auditor tenure. The industry specialist auditors mitigate earnings management more than nonspecialist auditors and don’t enhance audit quality through extending auditor tenure.