隨著企業財務弊案接連發生，導致投資人信心潰散，迫使人們不得不重視公司治理之議題，而自願性揭露即為公司治理機制下資訊透明度的表徵中相當重要的環節。公司治理機制的好壞將影響自願性揭露的水準。因此，本研究欲以公司治理內外部機制的角度，探討影響自願性揭露的因素。首先，本研究將所採用之揭露索引表先製作為問卷，以國內財務分析師為問卷發放對象，之後再根據所填答之結果增減揭露索引表之內容，以作為揭露評分項目，再依據各上市公司自願性揭露程度，瞭解各公司之公司治理機制的有效性。結果發現：獨立董（監）事比率愈高，自願性揭露程度愈高；董事長兼任總經理會傷害資訊揭露程度，此外，亦發現獨立董（監）事的存在能夠降低董事長兼任總經理對自願性揭露程度所帶來之傷害；在董事長兼任總經理的情況下，隨著家族成員佔董（監）事席次比率的提高，會加深公司於自願性揭露上之不足。
最後，本研究探討自願性揭露程度與公司績效間之關係，並且考慮變數間之內生性關係，而分別利用一般最小平方法與二階段最小平方法，期望解決過去研究中僅使用一般最小平方法所可能出現之估計偏誤之問題。實證結果顯示，隨著自願性揭露程度之提升，公司之財務績效（資產報酬率與每股盈餘）與市場績效（股票報酬率與Tobin’s Q）皆會隨著提高，甚至對於後續績效之影響亦甚明顯。此結果顯示出為公司於提供資訊揭露上，能帶來激勵之效果。

It is commonly agreed that there were numbers of accounting scandals that were not only the result of a loss in investor confidence but, more importantly, of a lack of effective corporate governance. Voluntary disclosure plays a major role in corporate governance. The purpose of this study is to examine the relationship between the effectiveness of corporate governance mechanisms, voluntary disclosure, and firm performance. First, this research’s disclosure index items were made as questionnaire and then sent to financial analysts in Taiwan. The purpose of this survey was to determine users’ perceptions of the usefulness of various voluntary disclosure items. According to the each listed company’s disclosure sore to observe the effective corporate governance mechanisms. The result shows that the level of voluntary disclosure increases if percentage of independent board director increases and the firms that have one individual who serves as both chairman and chief executive officer are more likely to have a lower extent of disclosure. Moreover, we also find that the negative association between CEO duality and the level of voluntary disclosure is weaker when the firms have a higher percentage of independent board directors.
Finally, this research adopts ordinary least squares, and two stage least squares to test the association between the level of voluntary disclosure and firm’s performance. The results support the following hypotheses. The level of voluntary disclosure has significantly positive effect on firm’s value. This result will encourage the firms to improve the level of voluntary disclosure.

第壹章  緒論	1
第一節	研究動機	1
第二節	研究目的	3
第三節	研究貢獻	3
第四節	研究流程	3
第貳章  文獻探討及假說發展	6
第一節	公司治理機制	6
第二節	自願性揭露與公司治理機制	10
第三節	自願性揭露與經營績效	12
第四節	研究架構	13
第五節	研究假說	14
第參章  研究方法	19
第一節	變數定義與衡量	19
第二節	資料搜集與樣本選取	23
第三節	資料分析方法	23
第肆章 實證結果分析	28
第一節  敘述性統計分析	28
第二節  迴歸分析	34
第伍章  結論與建議	56
第一節  結論	56
第二節  研究限制及未來研究方向	57
參考文獻	59

圖目錄
圖1-1	研究流程圖	5
圖2-1	研究架構圖	13

 
表目錄
表4-1樣本公司之產業分布表	28
表4-2問卷之敘述性統計量	30
表4-3實證變數之敘述性統計值	32
表4-4 PEARSON相關係數矩陣	33
表4-5公司治理機制與自願性揭露之迴歸模型結果	37
表4-6獨立董（監）事設置與否與自願性揭露之迴歸模型結果	38
表4-7公司治理機制與自願性揭露之迴歸模型結果	39
表4-8家族成員占董（監）事席次比例是否過半與自願性揭露之迴歸模型結果	40
表4-9家族成員占董（監）事席次比例過半與否與自願性揭露程度之平均數差異檢定	41
表4-10全體董（監）事持股比率分組後與自願性揭露之迴歸模型結果	42
表4-11總經理持股比率分組後與自願性揭露之迴歸模型結果	43
表4-12多重職位獨立董（監）事與自願性揭露之迴歸模型結果	44
表4-13自願性揭露與經營績效之二階段最小平方法模型結果	46
表4-14自願性揭露與經營績效之迴歸模型結果	46
表4-15董事會成員兼任公司內部其他職位與自願性揭露之迴歸模型結果	48
表4-16獨立董（監）事比例與總經理角色交互作用對自願性揭露之迴歸模型結果Ⅰ	51
表4-17家族成員佔董（監）事席次比例與總經理角色交互作用對自願性揭露之迴歸模型結果Ⅱ	52
表4-18內部人持股比例與與自願性揭露之迴歸模型結果	53
表4-19內部人持股比例與總經理角色交互作用對自願性揭露之迴歸模型結果Ш	54
表4-20自願性揭露與下一期經營績效之迴歸模型結果	55
表4-21自願性揭露與下一期經營績效之迴歸模型結果	55
附表	63
附錄一：揭露指引表	65

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