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In this paper, a pricing problem for corporate bond with dynamic default barrier is studied under a hybrid model. Firstly, a mathematical model for the pricing problem is set up by applying risk-free equilibrium principle. Then, a closed-form formula for the pricing model is obtained by using the variable transformation technique and the image method, which extends the relevant literature's results. Finally, a numerical experiment is presented to analyze the effect of the dynamic barrier on the bond price. Our studies show that the different shape curve of a bond's price can be obtained by adjusting the relevant parameter on the default boundary, and then can control the risk or get a higher bond's yield     

双晶形貌法观察Gal－xAlxAs／GaAs外延材料的内部缺陷

文章采用日本产的ＣＮ１５１１８及扫描型双晶形貌测角仪直接拍摄了ＭＢＥ生长的Ｇａｌ－ｘＡＬｘＡｓ／ＧａＡｓ外延层和衬底层的形貌像，观察到面层中存在失配位错，单方向位错线晶面取向差等缺陷。并比较了生长温度对外延层质量的影响。     

Exploring the evolution of complexity in signaling networks

Signaling networks are exemplified by systems as diverse as biological cells, economic markets, and the Web. After a discussion of some general characteristics of signaling networks, this article explores the adaptive evolution of complexity in a simple model of a signaling network. The article closes with a discussion of broader questions concerning the evolution of signaling networks. © 2002 Wiley Periodicals, Inc.     

信用违约互换的定价方法

通过对信用违约互换的结构的分析,在Merton的结构化方法框架下,用偏微分方程求出公司的违约概率密度,最后给出信用违约互换的一种定价方法.     

基于公司收益率的信用风险动态分析

将公司的净资产收益率看作是由公司的前一系列收益率数据和宏观经济因素共同影响下的变量,并使用VAR方法对宏观经济变量进行分析,建立了企业收益率的动态预测模型,由此对公司下一时刻的收益率进行预测,进而根据违约门限对违约概率进行了估计.     

具有一般跳幅度分布的跳扩散模型下永久公司债券的定价

在公司资产价值演化服从具有一般跳幅度分布的跳扩散模型下,采用结构化方法研究具有无限到期日公司债券的定价问题,通过微分方程的方法和无套利原理获得了公司债券,股东权益和公司总价值的定价表达式以及最佳违约边界的表达式.     

Optimal reinsurance with regulatory initial capital and default risk

In a reinsurance contract, a reinsurer promises to pay the part of the loss faced by an insurer in exchange for receiving a reinsurance premium from the insurer. However, the reinsurer may fail to pay the promised amount when the promised amount exceeds the reinsurer’s solvency. As a seller of a reinsurance contract, the initial capital or reserve of a reinsurer should meet some regulatory requirements. We assume that the initial capital or reserve of a reinsurer is regulated by the value-at-risk (VaR) of its promised indemnity. When the promised indemnity exceeds the total of the reinsurer’s initial capital and the reinsurance premium, the reinsurer may fail to pay the promised amount or default may occur. In the presence of the regulatory initial capital and the counterparty default risk, we investigate optimal reinsurance designs from an insurer’s point of view and derive optimal reinsurance strategies that maximize the expected utility of an insurer’s terminal wealth or minimize the VaR of an insurer’s total retained risk. It turns out that optimal reinsurance strategies in the presence of the regulatory initial capital and the counterparty default risk are different both from optimal reinsurance strategies in the absence of the counterparty default risk and from optimal reinsurance strategies in the presence of the counterparty default risk but without the regulatory initial capital.     

Modelling credit default swap spreads by means of normal mixtures and copulas

This paper develops a multivariate statistical model for the analysis of credit default swap spreads. Given the large excess kurtosis of the univariate marginal distributions, it is proposed to model them by means of a mixture of distributions. However, the multivariate extension of this methodology is numerically difficult, so that copulas are used to capture the structure of dependence of the data. It is shown how to estimate the parameters of the marginal distributions via the EM algorithm; then the parameters of the copula are estimated and standard errors computed through the nonparametric bootstrap. An application to credit default swap spreads of some European reference entities and extensive simulation results confirm the effectiveness of the method.     

Reflected BSDEs with random default time and related mixed optimal stopping-control problems

In this paper we study the one-dimensional reflected backward stochastic differential equations which are driven by Brownian motion as well as a mutually independent martingale appearing in a defaultable setting. Using a penalization method, we prove the existence and uniqueness of the solutions to these equations. As an application, we show that under proper assumptions the solution of the reflected equation is the value of the related mixed optimal stopping-control problem.     

带有违约风险的可转换债券的简约型定价

本文考虑简约模型下带有违约风险的可转换债券的定价问题.假定市场中可转换债券的违约强度满足Vasicek模型,利用鞅方法获得了该模型下可转换债券的定价公式.此外,我们通过数值分析显示了模型参数变化对可转换债券价值影响的敏感性程度,结果也表明违约风险将降低可转换债券的价值.