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arXiv · 1107.2716

Stability of exponential utility maximization with respect to market perturbations

Erhan Bayraktar·Ross Kravitz
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Abstract

We investigate the continuity of expected exponential utility maximization with respect to perturbation of the Sharpe ratio of markets. By focusing only on continuity, we impose weaker regularity conditions than those found in the literature. Specifically, we require, in addition to the $V$-compactness hypothesis of Larsen and Žitković (2007) (ArXiv: 0706.0474), a local $bmo$ hypothesis, a condition which is seen to always be trivially satisfied in the setting of Larsen and Žitković (2007). For markets of the form $S = M + \int λd $, these conditions are simultaneously implied by the existence of a uniform bound on the norm of $λ\cdot M$ in a suitable $bmo$ space.

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Erhan Bayraktar, Ross Kravitz. 2012-12-11. Stability of exponential utility maximization with respect to market perturbations. https://arxiv.org/abs/1107.2716

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