中文摘要：

股票市场IPO定价机制的完善是股票市场融资合理化和正确发挥市场资源配置功能的内在要求，也是我国股票市场发展的必然选择。利用随机微分理论并结合Hamilton-Jacobi-Bellman方程分析了我国不同时期新股定价机制对投资者新股投资决策的影响；通过对我国不同时期新股定价机制效率的分析，指出当前我国IPO定价机制的缺陷和不足。分析表明推进我国IPO定价机制的市场化改革，有助于缓解一、二级市场矛盾，提高投资理性，促进我国证券市场的不断成熟。

英文摘要：

The improvement of IPO pricing mechanisms is the inherent demand for the financing function and resources allocation function of the stock market and the inevitable trend for developing the stock market in China. We analyze how the pricing mechanism of IPO influences investors＇ decision-making with the Stochastic Equation and Hamihon-Jacobi-Bellman Equation. Based on the further analysis of the new stock pricing mechanisms in periods, the problems and limitations in our current IPO pricing mechanism has been pointed out. The different analysis suggests that the market-oriented reform of IPO Pricing Mechanism in China contributes to relieving the contradictions between the primary and secondary markets and increasing the rational investment so as to promote the improvement of stock market in China.