Some analyses of car insurance claim rates by make and size.

Data on the number of cars insured by an insurance company, and the claims experience for one year, have been analyzed. The policy data for any one make were found to be nonhomogeneous with respect to age, size of engine and type of policy cover. Data for the more popular makes were more homogeneous, and comparisons could be made of the effect on claim rate of age, size of engine and no claim bonus entitlement. There were higher claim rates for the newer vehicles, those with zero no claims bonus, and for two foreign makes and possibly for cars with larger engines. The variation of the rates about regression lines against age is consistent with the hypothesis that the number of claims follows a poisson distribution about a rate linearly related to age.