董事會獨立性、獨立董事忙碌程度、外部董事持股比例、董事會薪酬與公司績效之關係研究：以台灣上市櫃公司為例

過去文獻中，探討有關董事會獨立性、獨立董事忙碌程度、外部董事持股比例，以及董事會薪酬與公司績效之間的關係，並沒有一致的研究結果。因此，本研究旨在以台灣上市櫃公司為樣本，探討上述四大面向對於公司績效的影響，並對研究結果提出可能的解釋。本研究採用台灣上市櫃公司2016至2018年為期三年的資料，並以資產報酬率（ROA）以及公司價值（Tobin’s Q）作為公司績效的代理變數，進行實證分析。研究結果發現，外部董事比例與ROA之間呈現顯著的負向關係，本研究推論當外部董事比例增加時，雖然董事會的監督角色會逐漸發揮作用，但相對地，內部董事比例也會隨之下降，使得董事會的顧問角色逐漸弱化。另一方面，本研究發現當公司的資產規模愈大時，獨立董事忙碌程度與ROA之間的正向關係愈不明顯。此結論說明當公司規模愈大時，獨立董事因兼任其他公司職務所造成的忙碌效果，大於其聲譽效果，進而減損公司績效。而當公司的研發密集程度愈大時，會使得獨立董事忙碌程度與Tobin’s Q之間的正向關係愈明顯，符合企業資源需求假說。此外，本研究發現外部董事持股比例與ROA以及Tobin’s Q之間，皆呈現顯著的負向關係。本研究認為，此結論說明壕溝防守效果大於誘因聯盟效果，使得當外部董事持股比例愈高時，反倒會減損公司績效。最後，本研究以監督績效、監督複雜度、以及監督風險建構外部董事的應領薪酬模型，並以實際薪酬減去應領薪酬，算出外部董事的超額薪酬。實證結果發現，外部董事超額薪酬與ROA之間呈現顯著的正向關係，支持隱性合約觀點。

關鍵字

董事會特性；外部董事；忙碌董事；代理理論；超額薪酬；隱性合約

並列摘要

In the previous literature, there has been no consistent result on the relationship between board independence, independent director’s busyness, outside director shareholding, board compensation and firm performance. Therefore, this study investigates how the four aspects mentioned above influence firm performance. This study empirically analyzes this topic by using data collected from listed companies in Taiwan during the period of 2016-2018, and adopting ROA and Tobin’s Q as proxy variables of firm performance. The results indicate that there is a significant negative relationship between the proportion of outside directors and ROA, implying that the supervisory role of the board will be strengthened when the proportion of outside directors increases. However, the proportion of inside directors will also decline simultaneously, which may weaken the advisory role of the board. This study also found that the greater the firm size, the weaker the positive relationship between independent director’s busyness and ROA. This implies that when the firm grows larger, the busy effect of independent directors by taking up positions in other companies is greater than the reputation effect of independent directors, and further decreases firm performance. Moreover, the greater R D intensity is, the greater the positive relationship between independent director’s busyness and Tobin’s Q is, in consistent with the resource need hypothesis. In addition, this study found that there is a significant and negative relationship between outside director shareholdings and ROA, as well as Tobin’s Q. This result indicates that the entrenchment effect is greater than the incentive alignment effect, so that the higher the proportion of outside directors, the lower the firm performance. Lastly, this study builds a model to measure the reasonable pay of outside directors by introducing monitoring performance, monitoring complexity, and monitoring risk. After the actual pay deducted by reasonable pay, excessive pay of outside directors can be estimated. The results show that the excess compensation of outside directors is significantly and positively correlated with ROA, supporting the concept of implicit contract.