Kaunia: Integration and Interconnection of Islam and Science Journal
Vol. 21 No. 2 (2025)

Determination of Insurance Premiums Using The Optimal Bonus-Malus System with The Bayesian Method

Zahro, Fatichatu (Unknown)
Chasanah, Sri Istiyarti Uswatun (Unknown)
Abdullah, Syarif (Unknown)



Article Info

Publish Date
13 Mar 2026

Abstract

This study develops an optimal bonus–malus premium model within a Bayesian decision-theoretic framework. Claim frequency is modeled using a Poisson distribution, while the number of claims exceeding a predefined critical threshold is modeled conditionally using a Binomial distribution. The Poisson intensity parameter is assigned an Exponential prior distribution, while the Binomial probability parameter follows a Beta prior distribution. The Exponential and Beta distributions are applied to model parameters rather than to observed data, ensuring probabilistic consistency. Since the Exponential distribution is a special case of the Gamma distribution, the Bayesian updating process remains mathematically coherent. To illustrate the model, a dataset of 1,000 simulated motor vehicle policyholders is generated in R under specified distributional assumptions. The results indicate that premiums increase with the number of claims exceeding the critical value and decrease with longer claim-free duration. The proposed framework provides a coherent and flexible approach for premium determination in bonus–malus systems. However, the findings are based on simulated data and specific modeling assumptions, which may limit direct empirical generalization.  

Copyrights © 2025






Journal Info

Abbrev

kaunia

Publisher

Subject

Religion Biochemistry, Genetics & Molecular Biology Chemistry Mathematics Physics

Description

The aim of KAUNIA journal is to publish high-quality articles dedicated to all aspects of the latest outstanding developments in the field of Science, Mathematics, Education, Technology, and Religious Perspective Interconnect-Integration. The journal publishes articles, reviews, and research notes ...