几何平均下的水平重置期权定价

针对重置期权的风险对冲△跳现象,研究了一种亚式特征的水平重置期权的定价问题.首先在BS模型下用股票的几何平均价格作为水平重置期权执行价格重置与否的统计量,然后运用测度变换和鞅定价方法得到了风险中性定价公式,最后利用风险中性定价公式得出风险对冲△值的显示解,改进了水平重置期权的部分已有结果.     

跳扩散模型下一种创新的重置期权定价

首先在风险中性测度下建立股票价格的跳过程为Poisson过程,跳跃高度服从对数正态分布时股票价格的随机微分方程,利用期权定价的鞅方法推导得到了欧式重置看涨期权的价格以及一种创新的重置看涨期权的定价公式．最后给出了一个数值计算的例子,说明了创新的重置看涨期权价格要大于或等于传统的重置看涨期权和欧式看涨期权价格,并从理论上进行解释．     

随机利率下奇异期权的定价公式

在随机利率条件下,借助于测度变换获得了复合看涨期权的一般的定价公式,同时利用鞅理论和Girsanov定理,在利率服从于扩展的Vasicek利率模型时,得到了复合看涨期权精确的定价公式.用同样的方法,考虑了预设日期的重置看涨期权的定价问题,在利率服从同样的利率模型时,获得了重置看涨期权的定价公式.数值化的结果进一步说明了当利率遵循扩展的Vasicek利率模型时,B-S看涨期权的价格关于标的资产的价格是严格单调递增的,复合看涨期权的Geske公式是可以推广到随机利率的情况.     

股价服从指数O-U过程的多点重置期权定价

本文在风险中性定价原则下,得到了股价服从指数O-U(Ornstein-Uhlenbeck)过程的n个重置日期m个执行价格的重置期权定价,又在利率服从扩展Vasicek模型下,得到了n个重置日期m个执行价格的重置期权定价.     

债券受布朗运动驱动时幂型支付重置期权的定价

考虑完全的无套利市场环境下,基础股票支付连续红利,债券价格满足由布朗运动驱动的随机微分方程,对具有幂型支付的一种创新重置期权,以鞅论和随机分析为工具,得到了期权的定价公式.     

随机利率下服从分数跳-扩散模型的重置期权定价

假设利率服从扩展的Vasicek模型,标的资产价格服从分数跳-扩散过程,利用无套利理论与多元正态分布,导出了规定时间的重置期权的定价公式.     

国内外利率为随机的双币种重置型期权定价

双币种重置期权的特征是指在终端期T时的收益依赖于预先设定的t<,0>时刻标的资产的价格与执行价K>0(事先给定)的大小关系重新设置期权的执行价从而给出其定价,这种期权是投资于外国资产的一种合约,其风险不仅依赖外国资产价格的变化,还受外国货币的汇率以及国内外两种利率波动的影响,所以在实际应用方面十分广泛.本文首先就标的资...     

随机利率下重置期权的定价问题

研究了Vasiˇ↑cek型短期利率模型下重置期权（Reset Option）的定价和风险管理问题，借助多元正态分布函数，得到了一组显示公式和近似计算方法。     

规定水平下重置期权的有限差分解

利用Black—Scholes偏微分方程,结合重置期权与关卡期权的关系,建立了规定水平下的重置期权定价模型,最后运用C—N格式和θ法构造该模型的有限差分格式．     

双跳跃仿射扩散模型的几何平均型水平重置期权定价

在资产收益率及其波动率均满足随机跳跃且具有跳跃相关性的仿射扩散模型下,用广义双指数分布和伽玛分布分别刻画非对称性收益率及其波动率的跳跃波动变化,研究了具有几何平均特征的水平重置期权定价问题.通过Girsanov测度变换和多维Fourier逆变换方法,给出了此类重置期权定价的解析公式.最后,通过数值实例着重分析了联合跳跃参数及杠杆效应对水平重置看涨期权价格的影响,并对风险对冲特征作了分析.结果表明,上跳概率,跳跃频率,杠杆效应,收益率波动的两个跳跃参数和双跳跃相关系数对期权价格有正向影响,上跳和下跳幅度对期权价格有反向影响,而期权的风险对冲参数没有出现明显的跳跃现象.这说明文章建立的期权定价模型比经典Black-Scholes模型具有更好的实际拟合能力.     

具有固定敲定价格的算术平均亚式期权的计算

本文研究算术平均的欧式亚式期权.我们将充分利用偏微分方程的Fichera理论和边值问题的定解理论,求出了一个简单的近似解析表达式.经实际数据验算,有较满意的逼近结果,特别地,在部分区域内的计算效果好于文章[1].     

Pricing of American lookback spread options

We find the closed form formula for the price of the perpetual American lookback spread option, whose payoff is the difference of the running maximum and minimum prices of a single asset. We solve an optimal stopping problem related to both maximum and minimum. We show that the spread option is equivalent to some fixed strike options on some domains, find the exact form of the optimal stopping region, and obtain the solution of the resulting partial differential equations. The value function is not differentiable. However, we prove the verification theorem due to the monotonicity of the maximum and minimum processes.     

On the explicit evaluation of the Geometric Asian options in stochastic volatility models with jumps

In the present paper we provide a semiexplicit valuation formula for Geometric Asian options, with fixed and floating strike under continuous monitoring, when the underlying stock price process exhibits both stochastic volatility and jumps. More precisely, we shall work in the Barndorff-Nielsen and Shephard (BNS) model framework. We shall provide some numerical illustrations of the results obtained.     

An IMEX‐BDF2 compact scheme for pricing options under regime‐switching jump‐diffusion models

In this paper, an implicit‐explicit two‐step backward differentiation formula (IMEX‐BDF2) together with finite difference compact scheme is developed for the numerical pricing of European and American options whose asset price dynamics follow the regime‐switching jump‐diffusion process. It is shown that IMEX‐BDF2 method for solving this system of coupled partial integro‐differential equations is stable with the second‐order accuracy in time. On the basis of IMEX‐BDF2 time semi‐discrete method, we derive a fourth‐order compact (FOC) finite difference scheme for spatial discretization. Since the payoff function of the option at the strike price is not differentiable, the results show only second‐order accuracy in space. To remedy this, a local mesh refinement strategy is used near the strike price so that the accuracy achieves fourth order. Numerical results illustrate the effectiveness of the proposed method for European and American options under regime‐switching jump‐diffusion models.     

An analytic pricing formula for lookback options under stochastic volatility

In this work, an analytic pricing formula for floating strike lookback options under Heston’s stochastic volatility model is derived by means of the homotopy analysis method. The fixed strike lookback options can then be priced on the basis of the results of floating strike and the put–call parity relation for lookback options.     

Optimization of covered call strategies

We present a risk-return optimization framework to select strike prices and quantities of call options to sell in a covered call strategy. Covered calls of a general form are considered where call options with different strike prices can be sold simultaneously. Tractable formulations are developed using variance, semivariance, VaR, and CVaR as risk measures. Sample expected return and sample risk are formulated by simulating the price of the underlying asset. We use option market price data to perform the optimization and analyze the structure of optimal covered call portfolios using the S&P 500 as the underlying. The optimal solution is shown to be directly linked to the options’ call risk premiums. We find that from a risk-return perspective it is often optimal to simultaneously sell call options of different strike prices for all risk measures considered.     

Infinite reload options: Pricing and analysis

Infinite reload options allow the user to exercise his reload right as often as he chooses during the lifetime of the contract. Each time a reload occurs, the owner receives new options where the strike price is set to the current stock price. We consider a modified version of the infinite reload option contract where the strike price of the new options received by the owner is increased by a certain percentage; we refer to this new contract as an increased reload option. The pricing problem for this modified contract is characterized as an impulse control problem resulting in a Hamilton–Jacobi–Bellman equation. We use fully implicit timestepping and prove that the discretized equations are monotone, stable and consistent, implying convergence to the viscosity solution. We also derive a globally convergent iterative method for solving the non-linear discrete equations. Numerical examples show that both the exercise policy and the option value are very sensitive to the percentage increase in the reload strike.     

Exact volatility calibration based on a Dupire-type Call–Put duality for perpetual American options

This paper investigates the calibration of a model with a time-homogeneous local volatility function to the market prices of the perpetual American Call and Put options. The main step is the derivation of a Call–Put duality equality for perpetual American options similar to the equality which is equivalent to Dupire’s formula (Dupire in Risk 7(1):18–20, 1994) in the European case. It turns out that in addition to the simultaneous exchanges between the spot price and the strike and between the interest and dividend rates which already appear in the European case, one has to modify the local volatility function in the American case. To show this duality equality, we exhibit non-autonomous nonlinear ODEs satisfied by the perpetual Call and Put exercise boundaries as functions of the strike variable. We obtain uniqueness for these ODEs and deduce that the mapping associating the exercise boundary with the local volatility function is one-to-one onto. Thanks to this Dupire-type duality result, we design a theoretical calibration procedure of the local volatility function from the perpetual Call and Put prices for a fixed spot price x ₀. The knowledge of the Put (resp. Call) prices for all strikes enables to recover the local volatility function on the interval (0, x ₀) (resp. (x ₀, +∞)). We last prove that equality of the dual volatility functions only holds in the standard Black-Scholes model with constant volatility.      

THE REGULARITY OF THE FREE BOUNDARY FOR STRIKE RESET OPTION

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 parabolic variational inequality and the optimal reset strategy is the free boundary. The smoothness of the free boundary in some cases was showed in our article published in JDE. We would prove its smoothness in the other case in this paper by a generalized comparison principle for the variational inequality.