本研究檢驗了台灣獨立董事制度對於公司價值(Tobin’s Q)的因果關係。樣本採用2009年、2010年、2013年、2015年之非金融業台灣上市上櫃公司作為主要分析對象,利用雙重差分法在控制時間變動對於公司價值的影響後,以公司價值(Tobin’s Q)為被解釋變數來探討獨立董事制度是否使公司價值顯著提升。 本研究將符合獨立董事制度的公司分為自願型以及被強迫型兩者。實證結果顯示在符合政府要求之獨立董事制度後,不論是自願型以及被強迫型的公司,其公司價值增加皆大於控制組公司。透過被強迫型公司的實證結果,本研究確認政府確實能用獨立董事政策來增加公司價值。 另進一步研究發現,獨立董事制度對於超額控制高、資訊需求高的公司有較大的正向影響。
This paper examines the casual relation between the Taiwanese independent director policy and firm value measured by Tobin’s Q. Using the methodology of difference-in-difference and using the data from 2009, 2010, 2013, 2015 of non-financial public corporates, the empirical result shows that independent directors can impose higher firm value for companies adapting the policy. This research separates companies that conformed to the policy as self-volunteered and compelled. For both types of companies, by conforming to the regulation, the increase of firm value is significantly higher than firms in the control group (of which the adaption of the policy did not happen during the test period). The empirical result of the compelled type firms supports the casual relationship between the policy and increase of firm value. Furthermore, this paper also discovers that for firms having higher excess control and higher information need, the conformation to the policy has more significant positive impact to its firm value.