arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2202.02708math.PR
收藏

基于信息的方法:存在违约时间时信用风险资产的定价

Information-Based Approach: Pricing of a Credit Risky Asset in the Presence of Default Time

Mohammed Louriki

AI总结:

本研究扩展基于信息的资产定价框架,纳入发行方随机违约时间,推导信用风险资产及期权价格,证明相关停时的完全不可达性,适用于违约不可预测的金融市场场景。

摘要:

我们对Brody、Hughston与Macrina提出的基于信息的资产定价框架进行扩展,纳入资产发行方的随机破产时间。本模型引入了将在时刻T支付的无违约现金流$Z_T$,同时资产发行方的可能破产时刻$τ$与长度为$ν=τ\bigwedge T$、钉住点为$σZ_T$的布朗随机桥(其中$σ$为常数)生成的滤子相一致。变量$Z_T$与$τ$不一定相互独立,模型并不严格依赖将$τ$解释为破产时间的设定。我们推导了该资产的价格过程,并计算了相关期权的价格,价格过程的动力学满足扩散方程。采用P.-A. Meyer的方法,我们给出了$ν$的补偿子的显式计算结果。利用桥过程的特殊性质,我们还给出了$Z_T\mathbb{I}_{[ν,+\infty)}$的补偿子的显式表达式。所得结论凸显了停时$ν$的完全不可达性质,这一特征尤其适用于金融市场——在违约发生前,无法通过系统内的任何其他信号预测发行方的违约时间。

英文摘要:

We extend the information-based asset-pricing framework by Brody, Hughston \& Macrina to incorporate a stochastic bankruptcy time for the writer of the asset. Our model introduces a non-defaultable cash flow $Z_T$ to be made at time $T$, alongside the time $τ$ of a possible bankruptcy of the writer of the asset are in line with the filtration generated by a Brownian random bridge with length $ν=τ\wedge T$ and pinning point $σZ_T$, where $σ$ is a constant. Quantities $Z_T$ and $τ$ are not necessarily independent. The model does not depend crucially on the interpretation of $τ$ as a bankruptcy time. We derived the price process of the asset and compute the prices of associated options. The dynamics of the price process satisfy a diffusion equation. Employing the approach of P.-A.~ Meyer, we provide the explicit computation of the compensator of $ν$. Leveraging special properties of the bridge process, we also provide the explicit expression of the compensator of $Z_T\,\mathbb{I}_{[ν,+\infty)}$. The resulting conclusion highlights the totally inaccessible property of the stopping time $ν$. This characteristic is particularly suitable for financial markets where the time of default of a writer cannot be predictable from any other signal in the system until default happens.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑