中文摘要：

本文通过手工收集2004--2013年中国A股上市公司独立董事的主要工作所在地信息．实证检验了独立董事地理距离对公司代理成本的经验影响关系。本文发现，独立董事地理距离与公司的双重代理成本均呈现显著的U型曲线关系．意味着独立董事距离任职公司太远或太近都不利于其发挥监督职能．这种影响在国有企业和欠发达地区企业中表现得更为明显．说明地理距离对独立董事监督职能的影响会因公司的产权性质和外部的制度环境而存在强弱差异。此外，本文进一步发现独立董事与任职公司间的地理距离越远．其越可能缺席公司的董事会会议．从而提供了地理距离影响独立董事监督职能的直接履职行为证据。本文的研究既丰富了独立董事监督职能影响因素的研究文献，也把关于地理区位特征影响经济主体行为的研究扩展到了独立董事领域．相关研究结论能够帮助投资者和监管机构根据独立董事的地理区位特征更好地识别上市公司代理问题的严重性．也有助于加深理解和科学评价中国独立董事的治理行为及其治理效果。

英文摘要：

In this study, we manually collect the working place of independent directors in Chinese A-share listed firms from 2004--2013 to investigate the influence of independent directors＇ geographic distance oncorporateagency costs. We find that there is a U-shaped relationship between them, which indicates that it may go against the supervisionduty of independent directors if their geographic distance is too large or too small. In addition, compared with non-state-owned enterprises （NSOEs） and firms in developed areas, this U-shaped relationship is more pronounced in state-owned enterprises （SOEs） and firms in underdeveloped areas, suggesting that the influence strength of independent directors＇ geographic distance on their supervision duty is contingent to the nature of property fight and institutional environment. Furthermore, we find a lower attendance rate of distant independent directors, which provides a direct evidence of duty execution behavior for the influence of independent directors＇ geographic distance on their supervision duty. This study enriches the literature on the determinants of independent directors＇supervision duty, and expands the research boundary regarding the influence of geography on economic entities to independent directors. Meanwhile, our findingscan help investors and policymakersbetter recognize the severity of corporate agency conflicts throughindependent directors＇geographic distance. Finally, our findings canalso help us understand and evaluate the governance behavior and effectiveness of independent direetorsmore deeply and scientifically.