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arXiv · 1708.01890

Optimal Learning under Robustness and Time-Consistency

Larry G. Epstein·Shaolin Ji
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Abstract

We model learning in a continuous-time Brownian setting where there is prior ambiguity. The associated model of preference values robustness and is time-consistent. It is applied to study optimal learning when the choice between actions can be postponed, at a per-unit-time cost, in order to observe a signal that provides information about an unknown parameter. The corresponding optimal stopping problem is solved in closed-form, with a focus on two specific settings: Ellsberg's two-urn thought experiment expanded to allow learning before the choice of bets, and a robust version of the classical problem of sequential testing of two simple hypotheses about the unknown drift of a Wiener process. In both cases, the link between robustness and the demand for learning is studied.

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Larry G. Epstein, Shaolin Ji. 2017-08-06. Optimal Learning under Robustness and Time-Consistency. https://arxiv.org/abs/1708.01890

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