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Optimal proportional reinsurance to maximize an insurer’s exponential utility under unobservable drift

Published online by Cambridge University Press:  21 February 2023

Xiaoqing Liang*
Affiliation:
Hebei University of Technology
Virginia R. Young*
Affiliation:
University of Michigan
*
*Postal address: Departmnt of Statistics, School of Sciences, Hebei University of Technology, Tianjin 300401, P. R. China. Email: liangxiaoqing115@hotmail.com
**Postal address: Department of Mathematics, University of Michigan, Ann Arbor, Michigan, 48109. Email: vryoung@umich.edu

Abstract

We study an optimal reinsurance problem for a diffusion model, in which the drift of the claim follows an Ornstein–Uhlenbeck process. The aim of the insurer is to maximize the expected exponential utility of its terminal wealth. We consider two cases: full information and partial information. Full information occurs when the insurer directly observes the drift; partial information occurs when the insurer observes only its claims. By applying stochastic control and by solving the corresponding Hamilton–Jacobi–Bellman equations, we find the value function and the optimal reinsurance strategy under both full and partial information. We determine a relationship between the value function and reinsurance strategy under full information with the value function and reinsurance strategy under partial information.

Type
Original Article
Copyright
© The Author(s), 2023. Published by Cambridge University Press on behalf of Applied Probability Trust

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