Risk sharing for capital requirements with multidimensional security markets

by Felix-Benedikt Liebrich1 and Gregor Svindland2
1Department of Mathematics, University of Munich, Germany
(email: liebrich@math.lmu.de)

2Department of Mathematics, University of Munich, Germany
(email: svindla@math.lmu.de)


Abstract

We consider the risk sharing problem for capital requirements induced by capital adequacy tests and security markets. The agents involved in the sharing procedure may be heterogeneous in that they apply varying capital adequacy tests and have access to different security markets. We discuss conditions under which there exists a representative agent. Thereafter, we study two frameworks of capital adequacy more closely, polyhedral constraints and distribution based constraints. We prove existence of optimal risk allocations and equilibria within these frameworks and elaborate on their robustness.


Key words: Capital requirements, Polyhedral acceptance sets, Law-invariant acceptance sets, Multidimensional security spaces, Pareto optimal risk allocations, Equilibria, Robustness of optimal allocations


JEL Classification:  D52, D53, G12
Mathematics Subject Classification (2010):  91B16, 91B30, 91B32, 91B50