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Utility maximization under model uncertainty in discrete time. (English) Zbl 1378.91114

This paper establishes the existence of an optimal portfolio in a general discrete-time model with uncertainty about the underlying probabilistic model. A key feature is that the scenario set of possible probability measures need not be dominated by a single reference model. Existence of the optimizer is shown under a notion of no-arbitrage introduced in [B. Bouchard and M. Nutz, Ann. Appl. Probab. 25, No. 2, 823–859 (2015; Zbl 1322.60045)] for a utility function bounded from above. A counterexample illustrates that additional integrability assumptions are needed to obtain existence in the unbounded case.

MSC:

91G10 Portfolio theory
60G44 Martingales with continuous parameter
60H30 Applications of stochastic analysis (to PDEs, etc.)

Citations:

Zbl 1322.60045

References:

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