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471.
市场中重大信息的到达会引起股票价格的跳跃.假设关于标的股票的重大信息到达服从更新过程,利用套期保值和无套利的思想,研究了欧式期权的定价.给出了更新跳跃情况下股票的价格公式和欧式期权应满足的偏微分方程,用Feynman-Kac公式求得欧式买权的价格,并用计算结果进行了验证. 相似文献
472.
473.
Mai Huong Nguyen & Matthias Ehrhardt 《advances in applied mathematics and mechanics.》2012,4(3):259-293
In this work we investigate the pricing of swing options in a model
where the underlying asset follows a jump diffusion process. We focus on the
derivation of the partial integro-differential equation (PIDE) which will be applied
to swing contracts and construct a novel pay-off function from a tree-based pay-off
matrix that can be used as initial condition in the PIDE formulation. For valuing
swing type derivatives we develop a theta implicit-explicit finite difference scheme
to discretize the PIDE using a Gaussian quadrature method for the integral part.
Based on known results for the classical theta-method the existence and uniqueness
of solution to the new implicit-explicit finite difference method is proven. Various
numerical examples illustrate the usability of the proposed method and allow us
to analyse the sensitivity of swing options with respect to model parameters. In
particular, the effects of number of exercise rights, jump intensities and dividend
yields will be investigated in depth. 相似文献
474.
475.
中国外汇储备规模适度性研究与预测 总被引:9,自引:0,他引:9
2005年,我国的外汇储备已经达到8188.72亿美元,且在近几年呈高速增长的势态.我国的外汇储备是否过多,这种增长是否会继续,面对高额的外汇储备,我们应该采取怎样的态度和政策?利用1979年—2005年的年度数据,运用协整分析的方法对外汇储备及相关变量进行分析,并通过得出的结论对上述问题给出一个解答. 相似文献
476.
A marine cyanobacterial promoter was cloned to allow efficient foreign gene expression. This was carried out using chloramphenicol
acetyl transferase (CAT) as a marker protein. For rapid and simple measurement of CAT activity, a method based on a fluorescently
labeled substrate was improved by utilizing HPLC equipped with a flowthrough fluorescent spectrophotometer. This method was
used in conjunction with a newly constructed promoter probe vector. Cyanobacterial transformants, harboring plasmid containing
a cloned 2-kbp marine cyanobacterial genomic fragment, showed a 10-fold higher CAT activity, compared with that achieved using
the kanamycin-resistant gene promoter. From the sequence analysis of the cloned fragment, a putative promoter region was found. 相似文献
477.
In this paper we extend a reduced form model for the valuation of employee share options (ESOs) to incorporate employee departure, and company takeover. We also allow for performance linked vesting and other exotic features specific to ESOs. We clarify the assumptions underlying the reduced form model, and discuss their implications. We analyze the probabilistic structure of the model which includes an explicit characterization of the set of equivalent martingale measures, as well as the computation of the variance optimal martingale measure and the minimal martingale measure. Moreover, we deduce an additive decomposition of the relative entropy. Particular ESO specifications are studied emphasizing different aspects of the proposed framework. In this context, we also provide strict no-arbitrage bounds for ESO prices by applying optimal stopping. Furthermore, possible limitations of the proposed model are explored by examining departures from the crucial assumptions of no-arbitrage, i.e. by considering the effects of the employee having inside information. 相似文献
478.
Expression of Human hepatitis B virus surface antigen (HBsAg) gene in plant was reported for the first time. The recombinant plasmid pRoKⅡ-HBsAg was constructed by inserting HBsAg gene into the downstream of CaMV 35S promoter of binary vector pRoKⅡ and then introduced into Agrobacterium tumefaciens LBA4404. The kanamycin-resistant plants were obtained by Agrobacterium-mediated transformation system. It was shown that HBsAg gene was expressed in transgenic tobacco plants and their progenies by ELISA. The spherical particles of ψ 22 nm in the leaf extract of trangenic tobacco were observed by immunosorbent electron microscopy. 相似文献
479.
有供应方限制的临时价格折扣与最优存贮模型 总被引:1,自引:0,他引:1
供应方提供临时价格折扣,一般都附带特别定货量限制。购买方可在所提供折扣价格条件下从有限种订货量中选择最小的订货量,但不一定是最优订货量。本文提出有供应方限制的临时价格折扣条件下的最优存贮模型和订货策略。并给出应用实例。 相似文献
480.
In the present paper we analyse the American option valuation problem in a stochastic volatility model when transaction costs are taken into account. We shall show that it can be formulated as a singular stochastic optimal control problem, proving the existence and uniqueness of the viscosity solution for the associated Hamilton–Jacobi–Bellman partial differential equation. Moreover, after performing a dimensionality reduction through a suitable choice of the utility function, we shall provide a numerical example illustrating how American options prices can be computed in the present modelling framework. 相似文献