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arXiv · 1710.00231

Systemic risk in a mean-field model of interbank lending with self-exciting shocks

Anastasia Borovykh·Andrea Pascucci·Stefano la Rovere
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Abstract

In this paper we consider a mean-field model of interacting diffusions for the monetary reserves in which the reserves are subjected to a self- and cross-exciting shock. This is motivated by the financial acceleration and fire sales observed in the market. We derive a mean-field limit using a weak convergence analysis and find an explicit measure-valued process associated with a large interbanking system. We define systemic risk indicators and derive, using the limiting process, several law of large numbers results and verify these numerically. We conclude that self-exciting shocks increase the systemic risk in the network and their presence in interbank networks should not be ignored.

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Anastasia Borovykh, Andrea Pascucci, Stefano la Rovere. 2017-09-30. Systemic risk in a mean-field model of interbank lending with self-exciting shocks. https://arxiv.org/abs/1710.00231

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