- Current Issue - Ahead of Print Articles - All Issues - Search - Open Access - Information for Authors - Downloads - Guideline - Regulations ㆍPaper Submission ㆍPaper Reviewing ㆍPublication and Distribution - Code of Ethics - For Authors ㆍOnlilne Submission ㆍMy Manuscript - For Reviewers - For Editors
 Bounds for exponential moments of Bessel processes Bull. Korean Math. Soc. 2019 Vol. 56, No. 5, 1211-1217 https://doi.org/10.4134/BKMS.b180974Published online September 30, 2019 Cloud Makasu University of the Western Cape Abstract : Let $0<\alpha<\infty$ be fixed, and let $X=(X_t)_{t\geq0}$ be a Bessel process with dimension $0<\theta\leq1$ starting at $x\geq0$. In this paper, it is proved that there are positive constants $A$ and $D$ depending only on $\theta$ and $\alpha$ such that \begin{equation*} \mathbf{E}_x\Biggl(\exp\bigl[\alpha\max\limits_{0\leq t\leq\tau}X_t\bigr]\Biggr)\leq A\mathbf{E}_x\Biggl(\exp[D\tau]\Biggr) \end{equation*} for any stopping time $\tau$ of $X$. This inequality is also shown to be sharp. Keywords : Bessel processes, comparison principle, optimal stopping problem, Young inequality MSC numbers : Primary 60G40, 34A40, 60E15 Downloads: Full-text PDF   Full-text HTML