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arXiv · 2108.05791

Risk sharing under heterogeneous beliefs without convexity

Felix-Benedikt Liebrich
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Abstract

We consider the problem of finding Pareto-optimal allocations of risk among finitely many agents. The associated individual risk measures are law invariant, but with respect to agent-dependent and potentially heterogeneous reference probability measures. Moreover, we assume that the individual risk assessments are consistent with the respective second-order stochastic dominance relations. We do not assume their convexity though. A simple sufficient condition for the existence of Pareto optima is provided. The proof combines local comonotone improvement with a Dieudonn\'e-type argument, which also establishes a link of the optimal allocation problem to the realm of "collapse to the mean" results. Finally, we extend the results to capital requirements with multidimensional security markets.

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Felix-Benedikt Liebrich. 2021-08-12. Risk sharing under heterogeneous beliefs without convexity. https://arxiv.org/abs/2108.05791

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