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arXiv · 1811.05738

Optimal stopping of Brownian motion with broken drift

Ernesto Mordecki·Paavo Salminen
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Abstract

We solve an optimal stopping problem where the underlying diffusion is Brownian motion on $\bf R$ with a positive drift changing at zero. It is assumed that the drift $μ_1$ on the negative side is smaller than the drift $μ_2$ on the positive side. The main observation is that if $μ_2-μ_1>1/2$ then there exists values of the discounting parameter for which it is not optimal to stop in the vicinity of zero where the drift changes. However, when the discounting gets bigger the stopping region becomes connected and contains zero. This is in contrast with results concerning optimal stopping of skew Brownian motion where the skew point is for all values of the discounting parameter in the continuation region.

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Ernesto Mordecki, Paavo Salminen. 2018-11-14. Optimal stopping of Brownian motion with broken drift. https://arxiv.org/abs/1811.05738

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