中文摘要：

在非线性Black-Scholes模型下,研究了阶梯期权定价问题.首先利用多尺度方法,将阶梯期权适合的偏微分方程分解成一系列常系数抛物方程;其次通过计算这些常系数抛物型方程的解,给出了修正障碍期权的近似定价公式;最后利用Feymann-Kac公式分析了近似结论的误差估计.

英文摘要：

In this paper, the pricing problems of geometric average Asian options are studied under the nonlinear Black-Scholes model. Firstly, the partial differential equations for the Asian options are transformed into a series of parabolic equations with constant coefficients by the perturbation method of single-parameter. Secondly, the approximate pricing formulae of the geometric average Asian options are given by solving those parabolic equations with constant coefficients. Finally, the error estimates of the approximate solutions are given by using Green function.