強制輪調政策對會計師產業專精度之影響

Abstract

本研究探討強制輪調政策對會計師產業專精度之影響，並分析輪調是否改變客戶取得產業專家服務之可能性。以1996至2009年間台灣上市櫃公司為樣本，結合會計師與客戶雙視角，觀察2003年政策實施前後之變化。 研究依據客戶組合比率法，設計兩種產業專精度指標：其一衡量會計師當期查核集中度，其二保留前期查核產業以捕捉知識延續性。進一步透過平方項估計產業集中度，以呈現查核重心分布變化。實證方法採用普通最小平方法與羅吉斯迴歸，分別對產業專精度與客戶取得產業專家服務之機率進行檢驗，並控制會計師經驗、事務所規模與公司財務特性等干擾因素。 實證結果顯示，若僅觀察當期專精度，輪調與產業專精度及集中度呈現正向關聯，顯示會計師傾向於短期內聚焦於特定產業。然而，當考慮前期產業之變化後，輪調與專精度及集中度皆轉為顯著負向，反映產業知識延續中斷與專業累積受損。另從客戶視角觀察，輪調政策施行後，公司聘任產業專家會計師之機率顯著上升，顯示制度可能促進專業資源重新配置。本研究揭示輪調政策在提升審計獨立性與維持產業專業性間的制度張力，並強調政策設計應兼顧知識延續與市場效率，以確保審計品質之穩定與深化。

This study investigates the effect of mandatory audit partner rotation on auditor industry specialization. Using listed firms in Taiwan from 1996 to 2009, I investigate the effect of the 2003 mandatory auditor partner rotation rule from the perspectives of both auditors and their clients. This study uses two measures of auditor specialization: one is based on a snapshot of auditor specialization by year end and the other takes into account changes in an auditor’s specializing industry. Both measures are based on auditors’ client portfolio. I also investigate the level of an auditor’s concentration in certain industries. I find that after audit partners are required to rotate, their industry specialization increases when using the snapshot measurement. The results suggest that auditors increase the level of industry specialization. However, when yearly changes in industries are considered, mandatory audit partner rotation is followed by a decrease in industry specialization. The results suggest that mandatory audit partner rotation disrupt auditors’ knowledge building of the same industry overtime. When measuring industry specialization from the perspective of audit clients, I find that the likelihood of hiring an industry expert increases after mandatory audit partner rotation. The results imply a reallocation of specialist resources. Overall, my findings reveal a trade-off between audit independence and industry expertise, highlighting the need for policy designs that maintain knowledge continuity while enhancing audit quality.