Multidimensional Credibility With Time Effects - An Application to Commercial Business Lines

This paper considers Danish insurance business lines, for which the pricing methodology recently has been dramatically upgraded. A costly affair, but nevertheless the benefits greatly exceed the costs; without a proper pricing mechanism, you are simply not competitive. We show that experience rating improves this sophisticated pricing method as much as it originally improved pricing compared to a trivial flat rate. Hence, it is very important to take advantage of available customer experience. We verify that recent developments in multivariate credibility theory improve the prediction significantly and we contribute to this theory with new robust estimation methods, for time (in-)dependency