中文摘要：

中止决策能力是影响风险投资公司长期绩效的重要指标之一，然而现有中止决策方法忽视了风险项目发展过程中信息对项目价值的影响，从而影响了中止决策时机。针对该问题，本文首先从贝叶斯后验估计的角度提出了风险投资家后验概率的信号学习过程；然后运用动态规划方法，在确定对风险项目最优投资水平的基础上，给出了基于风险项目价值的最优中止时机模型；最后对最优中止时机模型进行了算例分析。本文提出的最优中止模型考虑了风险项目发展过程中新信息释放对中止时机的影响，解决了分阶段投资情形下的最优中止决策问题，为风险投资家及时做出中止决策提供决策依据。同时，该模型还可用来分析风险投资家对风险项目的最优投资水平问题，为其做出最优决策提供参考。此外，模型的分析也为风险项目创始人通常发生的逆向选择行为提供了合理的解释。

英文摘要：

The ability of making termination decision is an important index that influences the long performance of the venture capital firms＇ However, the present termination decision methods ignore the incoming information＇s effect during the venture project development process, thus influence the termination decision time. Aiming at this problem, from the view of Bayesian posterior estimate, this paper proposes the posterior probability signal learning process of venture capitalist firstly based on determining the optimal investment amount to venture project, it then presents a model of venture project＇s optimal termina- tion time based on venture project＇s value using the dynamic programming method and a numerical example which analyses the optimal termination time model is given lastly. The optimal termination model put forward in this paper considers the influence of the incoming information releasing on the termination time, and it deals with the termination decision problem in the case of stages. It also provides reference for venture capitalist to make termination decision. At the same time, this model can be also used to analyse venture capitalist＇s optimal investment decision to venture project, it also provides reference for venture capitalist＇s optimal decision. Besides, the analysis of model gives a reasonable explanation to the enterpriser＇s adverse selection behavior.