集團企業產業多樣化與審計產業專家之外溢效果

Industry Diversification of Business Groups and the Spillover Effect of Audit Industry Specialization

本文旨在探討集團企業之產業多樣化策略是否會影響集團之盈餘管理方式，以及相較於一般查核會計師，審計產業專家有較高之審計品質，故透過產業專家對於特定產業之專業查核知識與技巧，是否能對集團之查核產生外溢效果。本研究也進一步將集團企業之整體產業多樣化區分為相關多樣化與非相關多樣化，以釐清集團企業之內部組成若聚焦在特定少數產業之經營策略，是否會有不同之盈餘管理選擇。實證結果發現，當集團整體產業多樣化或非相關多樣化程度較高時，較不會透過裁決性應計數負值向下調整盈餘，也較不會使用實質盈餘管理；然而，若為產業專家查核時，較高程度之非相關多樣化較會操弄盈餘向下，且會受限於產業專家之高品質查核，無法透過應計項目盈餘管理調整盈餘向上，而需轉向進行對企業成本較高之實質盈餘管理；有趣的是，審計產業專家能抑制相關多樣化程度較高之集團企業透過放寬信用條件之方式進行實質盈餘管理，此為產業專家對特定產業之專業查核技巧發揮外溢效果之證據，本文於其他分析處也發現當受查之集團有高財務風險或會計師查核任期較長時，皆會有產業專家之外溢效果。希冀透過本文之實證結果，延伸目前文獻對於產業專家查核集團企業之發現，與未來相關研究更多思考的方向。

This article aims to examine whether a business group’s industry diversification strategy will affect the business group’s earnings management approach, and whether industry experts’ audit knowledge and techniques pertaining to specific industries can have a spillover effect on the business group’s audits given that industry specialist auditors have higher audit quality than general auditors. This study also further divides the overall industry diversification of business groups into related and unrelated diversification to determine if different earnings management options arise when the internal composition of business groups focuses on the operating strategy of specific minority industries. Empirical results show that when overall industry diversification or unrelated diversification is relatively high, a business group is less likely to adjust earnings downward through negative discretionary accruals, and is less likely to use real earnings management. However, during an industry specialist audit a higher degree of unrelated diversification may lead to more downward earnings manipulation, which is constrained by high-quality audits conducted by industry experts. Consequently, earnings cannot be adjusted upwards through accruals and need to be switched to real earnings management which incurs higher business cost. Interestingly, industry specialist auditors can inhibit business groups with high degrees of related diversification from implementing real earnings management under relaxed credit conditions. This demonstrates the spillover effect resulting from industry specialist audit techniques for specific industries. Additionally, this finds that other analysis exhibit spillover effects when audited business groups face high financial risk or when an auditor has a long tenure. We hope that the empirical findings of this study will contribute to literature on industry specialist auditors in business groups and provide guidance for future related research.