Abstract
We continue the study of utility maximization in the nonsmooth setting and give a counterexample to a conjecture made in Deelstra et al. (Ann. Appl. Probab. 11:1353–1383, 2001) on the optimality of random variables valued in an appropriate subdifferential. We derive minimal sufficient conditions on a random variable for it to be a primal optimizer in the case where the utility function is not strictly concave.
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This research was funded by an EPSRC grant.
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Westray, N., Zheng, H. Minimal sufficient conditions for a primal optimizer in nonsmooth utility maximization. Finance Stoch 15, 501–512 (2011). https://doi.org/10.1007/s00780-010-0128-6
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DOI: https://doi.org/10.1007/s00780-010-0128-6