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arXiv · 1411.0426

Risk measures with the CxLS property

Freddy Delbaen·Fabio Bellini·Valeria Bignozzi·Johanna F. Ziegel
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Abstract

In the present contribution we characterize law determined convex risk measures that have convex level sets at the level of distributions. By relaxing the assumptions in Weber (2006), we show that these risk measures can be identified with a class of generalized shortfall risk measures. As a direct consequence, we are able to extend the results in Ziegel (2014) and Bellini and Bignozzi (2014) on convex elicitable risk measures and confirm that expectiles are the only elicitable coherent risk measures. Further, we provide a simple characterization of robustness for convex risk measures in terms of a weak notion of mixture continuity.

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Freddy Delbaen, Fabio Bellini, Valeria Bignozzi, Johanna F. Ziegel. 2014-11-03. Risk measures with the CxLS property. https://arxiv.org/abs/1411.0426

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