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arXiv · 2010.15254

Dynamic Default Contagion in Heterogeneous Interbank Systems

Zachary Feinstein·Andreas Sojmark
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Abstract

In this work we provide a simple setting that connects the structural modelling approach of Gai-Kapadia interbank networks with the mean-field approach to default contagion. To accomplish this we make two key contributions. First, we propose a dynamic default contagion model with endogenous early defaults for a finite set of banks, generalising the Gai-Kapadia framework. Second, we reformulate this system as a stochastic particle system leading to a limiting mean-field problem. We study the existence of these clearing systems and, for the mean-field problem, the continuity of the system response.

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Zachary Feinstein, Andreas Sojmark. 2020-10-28. Dynamic Default Contagion in Heterogeneous Interbank Systems. https://arxiv.org/abs/2010.15254

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