实物期权在企业R&D 项目投资决策中的应用研究 蔚林巍  
清华大学经济管理学院  
weilw@tsinghua.edu.cn  

更新时间：2008-05-03   摘要: 
本文首先对过去几十年来实物期权方法应用研究进展进行了回顾和总结，并指出了目前在实物期权方法应用中经常出现的一些模糊概念和误用的问题。通过一些实例的分析和讨论，对现有的一些研究结论提出了质疑，指出：由于问题构模及参数定义上的差异，一些在金融期权中成立的定理，如期权价值随着波动率增加、无风险利率增大或期权期限延长时，是递增的这一规律对于实物期权的而言可能会失效。并以实物期权在企业R&D 投资项目中为例，对这一问题以及与之相关的实物期权构模和参数选择等问题进行了详细深入的讨论和分析。文章还在对Penning and Lint（1997）及Agliardi Elettra（2003）等人的结果扩展的基础上，给出了当波动率、无风险利率和期权持有成本为时变函数的条件下四种复合期权的解析解，并利用数值计算结果证实了作者的观点。 Abstract: This study first reviews the literature of real options research in the past decades, and points out the problem of obscure concepts and misuse of real option frequently appeared in the application fields. By analyzing and discussing some cases, the author put forward doubt on some research results, and indicate that because of the discrepancy of modeling and parameter definition, some theorems which true for financial options, such as the value of options will increase when the volatility and risk-free rate increase or expiration date suspension, will not true for the real options. Using the application of real options in firm’s R&D project as an example, the paper analyses and discusses the problem in detail how to applying real options from aspects of modeling, parameter estimation and sensitivity analysis correctly, etc. By extending the results of Penning and Lint (1997) as well as Agliardi Elettra (2003), a close-form solution for a generalized of the Geske formula is derived for four types compound real options: call on call, call on put, put on call, put on put in the case of time-dependent volatility and risk-free rate and option-holding cost. The author’s findings are proven by numerical results in the last.
关键字: 实物期权，R&D 项目投资决策，复合期权，Geske 公式，二项式模型； Key Words: Real Option; R&D investment; Compound Option; Geske formula; Binomial formula