股权激励的激励机制及其绩效解说

【作者】 张帆；

【导师】 石磊；

【作者基本信息】 复旦大学 ， 政治经济学， 2003， 博士

【摘要】 股权激励是现代西方发达国家在公司治理实践中广泛推行的新形式的经理人激励制度。与这种激励制度在实践中获得的广泛应用和巨大成功相比，国内外相关的理论研究却出现了相当程度的滞后：国外经济学界从委托——代理理论和融资结构契约理论的不同研究范式出发，对股权激励的激励机理存在长期的争论，二者都无法圆满地解释相应的实证研究结果；而国内经济学界对这一问题的讨论仍然处在从经典马克思政治经济学向西方主流经济学过渡的阶段，基本概念和命题的争论成为了研究的主要内容。显然，在股权激励的激励机制得到澄清并经过实证分析的验证之前，盲目引入这种制度并冀望于以此一劳永逸地解决我国企业内部治理问题无疑是一厢情愿的想法。于是，股权激励制度能否够改变公司的治理结构，它的实施究竟会从哪些方面对公司价值产生影响成为本文关注的重点。 本文认为，社会经济资源的配置在两个层面同时发生：在资本市场上以资本财富的形式流动和分配；在企业中以实际物质形态流动和分配。前者由资本市场上交易者的交易行为决定；后者由企业的经理人来决定。这样，当资本市场达到充分有效的均衡时，实际企业中的经济资源配置并不一定会达到帕累托最优：因为企业的经理人可能根本不会理会来自资本市场，包含在公司股票价格中的资源配置信号；反之亦然。但是，当对经理人实施股权激励之后，经理人在有效激励合同的诱导下，将会对上述资源配置信号做出反应。激励合约的真实作用在于，一方面向企业的委托人和代理人分别传递回溯性的经理人评价信息和前瞻性的资源配置信息；另一方面向资本市场传递反向的经理人私人信息，通过同时提高资本市场资金配置效率和实际经济资源的配置效率来提高企业的价值。这正是股权激励合约改善公司治理结构并影响经济运行效率，提高公司价值的机理所在。 在给出激励机制的理论解释之后，本文在霍姆斯特姆和利兰德、帕尔的单向信息传递模型的基础之上构建了一个双向信息模型来对上述过程进行数学描述。模型考察的重点在于经理人股权激励合约的设计：即，企业的委托人如何根据资本市场上公司股票价格变化来奖惩经理人，通过满足经理人参与约束条件和激励相容条件的激励合约来诱使经理人做出最大化公司价值的经营决策。在博弈决策树上，经理人必须选择努力制造信号或者积极吸收资本市场上的正确信号，才有可能获取高额的报酬。在这里，作者试图通过一个简化的模型来给出股权激励合约设计上的一般约束条件。 在充分讨论股权激励合约提高公司价值的正向作用机理的基础上，结合该激励制度对公司外部竞争性市场约束机制的损害，进一步讨论了实施股权激励制度对公司价值的综合影响，并应用相关结论较好地解释了国外有关的实证研究结果。但在本文随后对我国部分上市公司实施股权激励的激励效果进行实证检验后，发现本文的理论假说无法对某些实证结果进行解释。作者随后讨论了我国资本市场的有效性;以及在国有上市公司中，国有股股东缺位引起的经理人占有内部股东剩余控制权来补充解释实证研究的部分结论。 最后，作者考察了我国各类企业试行股权激励制度的相关做法和相应出现的问题。针对上述问题，对在我国有效推行股权激励制度给出了相关的政策建议。更多还原

【Abstract】 Executive stock option and making manager an inside shareholder is a new incentive mechanism widely used in western countries to mitigate principal-agent problems. Although utilizing such mechanism has achieved great success in corporation practices, economists never stop their suspicions on it. Foreign economists either discuss this issue from the perspective of principal-agent theory or from corporation finance theory, but they never get consensus with each other and whether this mechanism would increase corporation value or not is remain to be a controversial topic in academic domain. On the other hand, domestic economists are discussing this issue under the confliction of classic political economics of Marx and western main trend economics, the only thing they could do is to argue about the basic concepts and definitions and it is meaningless for us to understand the essence of this incentive system. It is obvious that we could not use this method to solve the principal-agent problem in Chinese enterprises permanently before we could clarify the working mechanism of this incentive system and testify it with positive research. That constitutes exactly what this dissertation concerns.The author thinks that economic resources are allocated simultaneously in two aspects: in capital market it is the allocation of capital fortune, and in the corporation it is the allocation of producing materials. The first allocation process is determined by the transactions in capital market and the latter one is at the disposal of corporation managers. So the secondary stock market prices, which is often viewed as the most "informationally efficient" prices in the economy, would have no direct role in the allocation of equity capital since managers have discretion in determining the level of investment because there is no incentive to induce managers to react upon such information.What is the link between stock price informational efficiency and economic efficiency? This dissertation present a model of the stock market in which: managers have discretion in making investments and must be given the right incentives and the stock market traders may have important information that managers do not have about the value of prospective investment opportunites and retrospective manager working exertions. In equilibrium, information in stock prices will not only guide investment decisions but also help the shareholders to evaluate manager’s work precisely: this all because managers compensation is linked with stock prices of the company and theinformation flow between capital market and managers are made possible. So we can realize the stock market efficiency and economic efficiency simultaneously by utilizing stock incentives to the corporation managers. In the model, the author gives out requirements for the manager’s compensational contract to satisfy the incentive compatibility and incentive constraint to induce managers to join such information producing and transferring process. By this way, we could reach Pareto dominance of economic resources allocation and maximize the value of the corporation.After depicting the mechanism of incentive system with our model, we discuss about making manager an inside shareholder would hamper competitive markets producing external pressure on corporate governance and thus would decrease corporation value. The author testifies this hypothesis by positive research on certain listed company in China and gives out theoretical explanations on research outcomes.Finally, the author probes into the practices of Chinese enterprises in utilizing stock incentives system to its managers and certain suggestions is given for the constitution of more efficient incentive system in China.更多还原