Killed Brownian motion with a prescribed lifetime distribution and models of default

Autor: Alexandru Hening, Boris Ettinger, Steven N. Evans
Jazyk: angličtina
Rok vydání: 2011
Předmět:
Zdroj: Ann. Appl. Probab. 24, no. 1 (2014), 1-33
Popis: The inverse first passage time problem asks whether, for a Brownian motion $B$ and a nonnegative random variable $\zeta$, there exists a time-varying barrier $b$ such that $\mathbb{P}\{B_s>b(s),0\leq s\leq t\}=\mathbb{P}\{\zeta>t\}$. We study a "smoothed" version of this problem and ask whether there is a "barrier" $b$ such that $ \mathbb{E}[\exp(-\lambda\int_0^t\psi(B_s-b(s))\,ds)]=\mathbb{P}\{\zeta >t\}$, where $\lambda$ is a killing rate parameter, and $\psi:\mathbb{R}\to[0,1]$ is a nonincreasing function. We prove that if $\psi$ is suitably smooth, the function $t\mapsto \mathbb{P}\{\zeta>t\}$ is twice continuously differentiable, and the condition $0t\}}{dt}
Comment: Published in at http://dx.doi.org/10.1214/12-AAP902 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Databáze: OpenAIRE