Ambiguity, also called Knightian or model uncertainty, is a key feature in financial modeling. A recent paper by Maccheroni et al. (2004) characterizes investor preferences under aversion against both risk and ambiguity. Their result shows that these preferences can be numerically represented in...

SFB 649 Discussion Paper 2005-051 Optimal Investments for Risk- and Ambiguity- Averse Preferences: A Duality Approach Alexander Schied* * Technische Universität Berlin, Germany This research was supported by the Deutsche Forschungsgemeinschaft through the...

Abstract We apply a suitable modification of the functional delta method to statistical functionals that arise from law-invariant coherent risk measures. To this end we establish differentiability of the statistical functional in a relaxed Hadamard sense, namely with respect to a suitably chosen...

Summary Robust utility functionals arise as numerical representations of investor preferences, when the investor is uncertain about the underlying probabilistic model and averse against both risk and model uncertainty. In this paper, we study the duality theory for the problem of maximizing the...