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arXiv · 2512.13562

Disability insurance with collective health claims: A mean-field approach

Christian Furrer·Philipp C. Hornung
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Abstract

The classic semi-Markov disability model is expanded with individual and collective health claims to improve its explanatory and predictive power -- in particular in the context of group experience rating. The inclusion of collective health claims leads to a computationally challenging many-body problem. By adopting a mean-field approach, this many-body problem can be approximated by a non-linear one-body problem, which in turn leads to a transparent pricing method for disability coverages based on a lower-dimensional system of non-linear forward integro-differential equations. In a practice-oriented simulation study, the mean-field approximation clearly stands its ground in comparison to na\"ive Monte Carlo methods.

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Christian Furrer, Philipp C. Hornung. 2025-12-15. Disability insurance with collective health claims: A mean-field approach. https://arxiv.org/abs/2512.13562

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