Arbitrage-free catastrophe reinsurance valuation for compound dynamic contagion claims
Jiwook Jang, Patrick J. Laub, Tak Kuen Siu, Hongbiao Zhao
TL;DR
This work develops an arbitrage-free framework for pricing catastrophe stop-loss reinsurance under a dynamic contagion model of aggregate losses. It constructs a compound dynamic contagion process (CDCP) with time-inhomogeneous extension to capture both conventional and emerging catastrophe risks, and employs the Esscher transform to define an equivalent martingale measure for risk-neutral pricing. The method yields closed-form tilts in a special exponential/gamma setting and uses Monte Carlo simulation to compute arbitrage-free premiums, with sensitivity analyses over the Esscher parameters and retention level. The results demonstrate that the arbitrage-free (gross) premiums exceed net premiums and show how parameter choices reflect market conditions, enabling practitioners to price catastrophe risk in the presence of climate, cyber, and pandemic risks. The approach offers a versatile tool for pricing catastrophe derivatives and can be extended to broader insurance-derivative applications.
Abstract
In this paper, we consider catastrophe stop-loss reinsurance valuation for a reinsurance company with dynamic contagion claims. To deal with conventional and emerging catastrophic events, we propose the use of a compound dynamic contagion process for the catastrophic component of the liability. Under the premise that there is an absence of arbitrage opportunity in the market, we obtain arbitrage-free premiums for these contacts. To this end, the Esscher transform is adopted to specify an equivalent martingale probability measure. We show that reinsurers have various ways of levying the security loading on the net premiums to quantify the catastrophic liability in light of the growing challenges posed by emerging risks arising from climate change, cyberattacks, and pandemics. We numerically compare arbitrage-free catastrophe stop-loss reinsurance premiums via the Monte Carlo simulation method. Sensitivity analyzes are performed by changing the Esscher parameters and the retention level.
