美式利率期权的最佳实施边界的分析

在Vasicek利率模型的假设下,应用变分不等式方法分析了美式利率期权自由边界的性质．首先我们得到美式利率期权自由边界的下界, 然后把自由边界问题化为变分不等式,通过引入惩罚函数证明了该变分不等式解的存在唯一性,最后证明了自由边界的单调性、 有界性和C∞光滑性．     

源于俄式期权定价的自由边界问题

本文主要应用PDE方法对俄式期权定价问题进行理论分析. 类似于美式期权定价问题,俄罗斯期权定价问题可归结为-个-维抛物型变分不等式.我们首先引入惩罚函数证明了该变分不等式的解的存在唯-性,然后研究了自由边界的一些性质,如单调性、光滑性和自由边界的位置.     

美式期权定价问题的数值方法

本文研究美式股票看跌期权定价问题的数值方法。通过将问题转化为等价的变分不等式方程，分别建立了半离散和全离散有限元逼近格式。并给出了有限元解的收敛性和稳定性分析。数值实验表明本文算法是一个高效和收敛的算法。     

基于美式障碍期权定价的非线性变分不等式问题

研究了一类基于美式障碍期权定价的非线性变分不等式问题.首先定义了变分不等式问题的弱解.其次利用惩罚方法和Schaefer不动点定理证明了该变分不等式在弱意义下的解是存在且唯一的.     

美式期权自由边界的计算方法

美式期权的自由边界问题在金融工程文献中已经引起了广泛的关注,然而,它的数值计算方法一直是一个难点.基于差分技巧,给出了满足具有有限到期日的美式期权自由边界的两种计算方法,即,根据股票期权价格和相应的偏导数来确定自由边界条件.数值结果表明了上述两种方法下自由边界是一致性的.此外研究结果对自由边界的计算提供很好的科学依据.     

美式期权定价问题的变网格差分方法

本文提出一种求解美式期权定价自由边值问题的变网格差分方法.通过建立一个自由边界所满足的方程,利用变网格技术可同时求出期权的差分解和最佳执行边界.本文分别讨论了显式和隐式变网格差分格式,并给出了差分解的收敛性和稳定性分析.数值实验表明本文算法是一个非常有效的期权定价算法.     

美式期权定价的数值方法

介绍了定价美式期权的几种常见数值方法.对最近几年的主要研究成果做了简单的介绍和比较,并给出了数值算例.特别回顾了美式期权定价的蒙特卡罗模拟加速方法.     

关于广义变分不等式与广义拟变分不等式

本文在非常一般的框架下,建立了极大极小不等式,广义变分不等式和广义拟变分不等式,证明了解的存在定理,且它们是在非紧集上得到的,从而推广和改进了[3～13]中的相应结果.     

A variational inequality arising from European option pricing with transaction costs

In this paper we present a method which can transform a variational inequality with gradient constraints into a usual two obstacles problem in one dimensional case.The prototype of the problem is a parabolic variational inequality with the constraints of two first order differential inequalities arising from a two-dimensional model of European call option pricing with transaction costs.We obtain the monotonicity and smoothness of two free boundaries.     

A variational inequality arising from American installment call options pricing

In this paper we consider a parabolic variational inequality with two free boundaries arising from American continuous-installment call options pricing. We prove the existence and uniqueness of the solution to the problem. Moreover, we obtain the monotonicity and smoothness of two free boundaries and show its numerical solution by the binomial method.     

A system of variational inequalities arising from finite expiry Russian option with two regimes

In this paper we consider a system of variational inequalities arising from the value of finite expiry Russian option with two regimes. We achieve the existence and uniqueness of the solution to the problem. Moreover, we show that the free boundaries are infinitely differentiable and monotonic with respect to time and some parameters in this system, as well as the mutual relationship between the solutions in two regimes. Moreover, we establish the bound of the free boundaries and analyze their property as time converges to infinite. Copyright © 2009 John Wiley & Sons, Ltd.     

A parabolic variational inequality arising from the valuation of strike reset options

A strike reset option is an option that allows its holder to reset the strike price to the prevailing underlying asset price at a moment chosen by the holder. The pricing model of the option can be formulated as a one-dimensional parabolic variational inequality, or equivalently, a free boundary problem, where the free boundary just corresponds to the optimal reset strategy adopted by the holder of the option. This paper is concerned with the theoretical analysis of the model. The existence and uniqueness of the solution are established. Furthermore, we study properties of the free boundary. The monotonicity and C^∞ smoothness of the free boundary are proven in some situations.     

American put option with regime‐switching volatility (finite time horizon)—Variational inequality approach

We study the fair price of American put option with regime‐switching volatility. Assuming that volatility σ(t) takes two different values σ₁ and σ₂, applying Δ hedging technique we obtain a system of evolutionary variational inequalities, which possesses two free boundaries (optimal exercise boundaries). The following are the main results of this paper.

• 1. Two free boundaries are monotonic and infinitely differentiable.
• 2. The optimal exercise boundary of American put option with regime‐switching volatility in the bearish (or bullish) market is smaller (or higher) than the one of standard American put option. And the price of American put option with regime‐switching volatility in the bearish (or bullish) market is higher (or smaller) than the one of standard American put option.
• 3. The solution of problem (1) is unique.

These results are original in the option pricing with regime‐switching volatility, the proof is technical. Copyright © 2008 John Wiley & Sons, Ltd.     

A free boundary problem arising from pricing convertible bond

In this article we study the behaviours of the optimal conversion boundary (i.e. free boundary) of an American-style convertible bond with finite horizon (i.e. parabolic case). We prove the existence and the uniqueness of the strong solution of the problem and the boundedness and smoothness of the free boundary. Moreover, we characterize the free boundary's start point and present two numerical results.     

A parabolic variational inequality related to the perpetual American executive stock options

A parabolic variational inequality is investigated which comes from the study of the optimal exercise strategy for the perpetual American executive stock options in financial markets. It is a degenerate parabolic variational inequality and its obstacle condition depends on the derivative of the solution with respect to the time variable. The method of discrete time approximation is used and the existence and regularity of the solution are established.     

An inverse coefficient problem for a nonlinear parabolic variational inequality

This study is related to inverse coefficient problems for a nonlinear parabolic variational inequality with an unknown leading coefficient in the equation for the gradient of the solution. An inverse method, involving minimization of a least-squares cost functional, is developed to identify the unknown coefficient. It is proved that the solution of the corresponding direct problem depends continuously on the coefficient. On the basis of this, the existence of a quasisolution of the inverse problem is obtained in the appropriate class of admissible coefficients.