市场化程度、独立董事独立性与公司价值——基于独立董事辞职公告的实证检验

Marketization,Independence of Independent Directors and Firm Value——Evidence from the Resignation Announcement of Independent Directors

本文以独立董事辞职公告为切入点,实证检验市场化程度、独立董事独立性与公司价值的关系。实证结果表明,独立董事的独立性有助于提升公司价值。如果独立董事的任职时间早于现任董事长,则辞职公告的市场反应较差;独立董事的任期越短,则辞职公告的市场反应越差。进一步的研究发现,市场化程度越高的地区,独立董事独立性与辞职公告市场反应之间的负相关关系越弱,这表明,独立董事的监督作用与市场化程度具有某种程度的替代性。

The original intention of independent director system is to solve the principal-agent problem between shareholders and managers. However, whether independent director really play the monitoring role, and provide a valuable service to shareholders？ Whether independent directors enhance the value of the company？ The existing lit- erature conclusions are quite different, even conflicting. There may be two reasons that lead the arguments, on the one hand, the board of directors is endogenously determined mechanism, the poor performance of the company will lead the board of directors to increase the independent directors （Hermalin and Weisbach, 2003 ） ; on the other hand, not all of the independent directors can effectively supervise the management, because the CEO may inter- vene in the hiring of independent directors （ Shivdasani and Yermack, 1999）. The same problem also exists in Chi- na; consequently the effectiveness of the system of independent directors is doubtful. In order to solve the above problems, the scholars have adopted the event study methodology to research the problem（ Nguyen and Nielsen, 2010）. Based on previous studies, this paper firstly explorers the market reaction to the independent director＇s resignation announcement, then examines the relationship between independence of inde- pendent directors and firm value, and analyzes how external governance environment （ the degree of regional mar- kets） affecting this relationship. We manually collect independent director resignation announcement between 2004 and 2010 from Shanghai and Shenzhen stock exchanges websites. We construct two variables to measure independ- ence of independent directors, that is relative tenure of independent directors （ Indepl ） and absolute tenure of in- dependent directors （Indep2）. The empirical results show that, the independence of independent directors is help- ful for improving firm value. If independent directors entered the board earlier than the current chairman of the board, then stock price will fall down after the announcement of independent director resignation. There exists a positive relationship between tenure of independent director and market reaction of resignation announcement. Fur- ther research finds that, the marketization will weaken the relationship between independence of independent direc- tors and market reaction of independent director resignation. This indicates that the marketization has some degree of alternative on supervisory role of independent directors. The conclusions of this study is similar to Zhang and Zeng （2010）, indicates that independent directors resig- nation announcement does have information content. On the other hand, this paper has deepened previous re- search, which is reflected in two aspects ： First, we integrate market reaction to announcement of the resignation of independent directors with independent directors background characteristics, and adopt two indicators to measure independence of independent directors, then examines the relationship of the independent directors＇ independence and firm value. Second, our study further discuss external governance environment （that is the degree of regional markets）, and conclude the supervisory role of the independent directors and the degree of marketization is alterna- tive in some degree, which enrich research of the relationship between of internal and external governance mecha- nisms. According to the paper, we propose two policy recommendations. First, regulators should consider limiting the number of independent directors in the nomination of large shareholders and management, and increasing the number of independent directors which behave minority shareholders. Second, it is necessary stipulate independent directors to serve only two consecutive terms.