When Indemnity Insurance Fails: Parametric Coverage under Binding Budget and Risk Constraints
Benjamin Avanzi, Debbie Kusch Falden, Mogens Steffensen
TL;DR
This paper shows that in high-risk environments where indemnity insurance is unaffordable or impractical, parametric insurance can yield higher welfare for risk-averse individuals under a mean-variance objective. By explicitly modeling frequency via a compound Poisson process and severity with censored exponential tails, the authors derive closed-form optimal contracts and premiums, highlighting a dual relation where E[Y_i] = d^* + k^* under Poisson frequency and equal loadings. The analysis demonstrates that parametric coverage remains welfare-enhancing particularly under binding premium budgets, with a non-monotonic pattern: parametric dominates at low budgets but loses its edge as budgets widen and indemnity becomes feasible. Policy implications emphasize recognizing parametric instruments as complementary risk-transfer tools that can speed payouts, support resilience, and complement public disaster relief, especially when traditional indemnity markets fail the affordability test.
Abstract
In high-risk environments, traditional indemnity insurance is often unaffordable or ineffective, despite its well-known optimality under expected utility. We compare excess-of-loss indemnity insurance with parametric insurance within a common mean-variance framework, allowing for fixed costs, heterogeneous premium loadings, and binding budget constraints. We show that, once these realistic frictions are introduced, parametric insurance can yield higher welfare for risk-averse individuals, even under the same utility objective. The welfare advantage arises precisely when indemnity insurance becomes impractical, and disappears once both contracts are unconstrained. Our results help reconcile classical insurance theory with the growing use of parametric risk transfer in high-risk settings.
