抑制代理成本提升公司价值了吗？——来自沪、深两市非金融类A股上市公司的经验证据

以沪、深两市非金融类A股上市公司2005～2009年的混合数据为研究对象，运用双变量回归（bivariate regression）、复回归（multiple regression）及协方差回归（ANACOVA）等计量方法，实证考察权益代理成本与公司价值间的关联性。研究结果表明，当权益代理成本降低时，我国上市公司的市场价值（托宾Q值）和财务业绩（ROA）均得到显著提高；且在引入内外部监督机制、管理层激励机制及股权结构特征三重约束后，二者的反向关联性仍维持稳定。此结论为代理成本理论增添了新的经验证据，即提升上市公司自身价值，保障投资者权益的有效途径之一就是降低代理成本。

Do Inhibition of the Agency Costs up to Enhance Corporate Value？ -From Shenzhen and Shanghai A-share Listed Non-Financial Companies Empirical Evidence

Using the bivariate regression model, multiple regression model, and ANACOVA model, this paper tests the relationship between equity agency costs and the firm value empirically. In a Shanghai and Shenzhen A-share listed non-financial companies＇ sample of 5268 firm-year observations during the period 2005-2009, we find that firms with higher market value （measured with Tobin＇s Q ） and financial performance （measured with ROA） when firms＇ equity agency eosts reduction. And after the introduction of the internal ＆ external supervision mechanisms, management incentives and equity structure as the triple constraint, the inverse relationship between the two remained stable. This conclusion adds new empirical evidence to the agency costs theories, which reducing agency costs, is one effective way to enhance their own value of firms and protect investors＇ legal rights.