我國從2003年起,開始採行上市櫃公司資訊揭露評鑑系統,然前人研究常單獨探討上市櫃公司於實施資訊揭露評鑑系統後,公司盈餘管理程度的差異性,忽略當時間、市場整體因素(公司治理機制的提倡)對所有公司盈餘管理程度的影響,以致於未能準確探討資訊揭露評鑑系統該項政策之有效性;故本研究以未受資訊揭露評鑑系統影響的興櫃及公開發行公司做為控制組,並採用差異中之差異法(Difference in Difference,DID)進行分析,來得到資訊揭露評鑑系統精確的政策效果。主要探究實施資訊揭露評鑑系統該政策對於上市櫃公司及興櫃、公開發行公司盈餘管理兩者間是否存有顯著差異性;更進一步檢測若公司自願性揭露更多資訊予外部大眾,其盈餘管理降低幅度是否更為顯著;此外,討論對盈餘管理程度較高產業的影響。研究發現如下: 發現修正資訊揭露評鑑系統後,受政策影響之上市櫃公司其盈餘管理降低幅度較不受政策影響的興櫃及公開發行公司更為明顯;然而,不論修正資訊揭露評鑑系統前後,對於均接受資訊揭露評鑑系統影響的上市櫃公司,自願性揭露程度高低公司在盈餘管理行為沒有顯著差異;此外,上市櫃電子業在資訊揭露評鑑系統實施後盈餘管理降低程度不如預期,反而修正資訊揭露評鑑系統後,盈餘管理程度卻顯著增加,凸顯我國資訊揭露評鑑系統仍有改善之必要。
Since 2003 Taiwan has been adopting Information Disclosure Ranking System to evalu-ate listed and OTC firms’ information transparency. Thus so far, previous studies usually ig-nored marketing factors which impact on earning management, such as corporate governance, result in they were unable to assess exactly the effect of policy. Therefore, we make use of Emerging Stock companies as a control group, using Difference in Difference(DID) to analy-sis. We focus on the earning management difference with listed and OTC firms and Emerging Stock companies. And if listed and OTC firms have been classified high level of voluntary disclosure, its earning management may reduce more than the other listed and OTC firms. In addition, discussing higher level of earning management industry’s the impact. Empirical re-sults indicate as follows: After revising of Information Disclosure Ranking System improves certainly earning management of listed and OTC firms which differs with Emerging Stock companies. However, compare between Information Disclosure Ranking System voluntary disclosure higher and lower enterprise, its earning management behavior has not certainly re-vealed the difference. After implementing Information Disclosure Ranking System, Electron-ics Industries’ earning management of listed and OTC firms have not anticipated results.