10.4225/03/5935ff417965f
Kalb, Guyonne R. J.
Kofman, Paul
Vorst, Ton C. F.
Mixtures of Tails in Clustered Automobile Collision Claims
2017
Monash University
1959.1/36020
1995
monash:6906
2017-06-06 01:02:56
article
https://monash.figshare.com/articles/Mixtures_of_Tails_in_Clustered_Automobile_Collision_Claims/5080564
Knowledge of the tail shape of claim distributions provides important actuarial information. This paper discusses how two techniques commonly used in assessing the most appropriate underlying distribution can be usefully combined. The maximum likelihood approach is theoretically appealing since it is preferable to many other estimators in the sense of best asymptotic normality. Likelihood based tests are, however, not always capable of discriminating among non-nested classes of distributions. Extremal value theory offers an attractive tool to overcome this problem. A much larger set of distribution classes is nested by their tail parameter. This paper shows that both estimation strategies can be usefully combined when the data generating process is characterized by strong clustering in time and size. We find that the extreme value theory is a useful starting point in detecting the appropriate distribution class. Once that has been achieved, the likelihood-based EM-algorithm is proposed to capture the clustering phenomena. Clustering is particularly pervasive in actuarial data. An empirical application to a four-year data set of Dutch automobile collision claims is therefore used to illustrate the approach.