本文旨在探討在2007年美國證管會允許外國公司無需在年報中揭露依美國一般公認會計原則編製之盈餘及股東權益調節數後，在美國上市之外國公司依照國際財務報導準則編製財務報表可能產生的盈餘管理活動，並比較在此新制實施後，較可能受此新制影響之公司（自願採用國際財務報導準則者）和自願採用美國一般公認會計準則之公司兩者間之盈餘管理策略是否存在差異。本研究發現前述兩類公司之裁決性應計數和實質盈餘管理（異常生產成本和裁決性費用）間具有同時發生的替代關係。然而， 相較於美國證管會新制實施後自願採用國際財務報導準則之公司，本文之增額測試發現新制實施前自願採用國際財務報導準則之公司，於同時間（資產負債表日前）和前後不同時間（資產負債表日前後）認列裁決性應計數和執行實質盈餘管理來達到預期之盈餘目標，並發現被所屬國家強制要求採用國際財務報導準則之公司，不會同時運用裁決性應計數和裁決性費用來進行盈餘管理。本文並發現經理人的報導動機（如「洗大澡」、盈餘平穩化、債務契約限制）影響裁決性應計數和實質盈餘管理兩者間之取捨，但是對於在新制實施後自願採用國際財務報導準則者而言，債務契約之存在和限制對於該二盈餘管理工具間之取捨，似乎扮演微不足道的角色。本研究之實證結果可做為檢測會計制度變革之影響時，需將報導動機和盈餘管理策略做結合探討之重要依據。

We investigate the earnings management potential of allowing non-U.S. cross-listed firms to choose International Financial Reporting Standards (IFRS) reporting following the Securities and Exchange Commission’s (SEC’s) elimination of the IFRS-to-U.S.-GAAP reconciliation requirement in 2007. We also investigate whether differences exist between earnings management strategies for firms whose filing choice is most likely attributable to the SEC’s regulatory change (i.e., firms that switched to IFRS voluntarily from local standards after the elimination) and those for firms that adopted U.S. GAAP voluntarily after the elimination. We find evidence of simultaneity and substitution between discretionary accruals and real activities manipulation (i.e., abnormal production costs and discretionary expenditures) for the two test samples of IFRS adopters and U.S. GAAP adopters. Nevertheless, in contrast to strategies for voluntary IFRS adopters after the elimination, our findings from additional analyses reveal that simultaneous (before the balance sheet date) and sequential (after the balance sheet date) decision processes (i.e., recognizing discretionary accruals and real activities manipulation in order to achieve expected earnings targets) co-exist in firms voluntarily adopting IFRS prior to the regulatory change, and that mandatory IFRS adopters do not manage earnings through discretionary accruals and discretional expenditures simultaneously. We also provide evidence that executives’ reporting incentives, which include “big bath”, income smoothing, and debt covenant restrictions, appear to affect the trade-off decision between discretionary accruals and real activities manipulation. However, the existence and tightness of accounting-based debt covenants seem to play a minor role in this decision for firms that switched to IFRS voluntarily after the elimination. Our empirical results underscore the importance of incorporating reporting incentives and earnings management strategies when examining the effects of regulatory changes in accounting standards.