Abstract
Optimal stopping of diffusions and related processes is usually done by solving a free boundary problem. In this paper, we propagate an alternative way, which has already been described in two earlier papers of Beibel and Lerche; we call it the B–L approach. It can be viewed as optimal stopping via measure transformation. While we emphasized in Beibel and Lerche a rather algebraic view, we describe here more the analytic side of the approach. Finally, it is related to some recent Jamshidian's results on a duality in optimal stopping.
Acknowledgements
The authors are grateful to F. Jamshidian for helpful discussions and valuable suggestions and to anonymous referees whose comments helped to improve the paper.
Notes
§This paper was written while the second author held a research fellowship of the Alexander von Humboldt-Stiftung.