Insurance {MASS}  R Documentation 
Numbers of Car Insurance claims
Description
The data given in data frame Insurance
consist of the
numbers of policyholders of an insurance company who were
exposed to risk, and the numbers of car insurance claims made by
those policyholders in the third quarter of 1973.
Usage
Insurance
Format
This data frame contains the following columns:
District

factor: district of residence of policyholder (1 to 4): 4 is major cities.
Group

an ordered factor: group of car with levels <1 litre, 1–1.5 litre, 1.5–2 litre, >2 litre.
Age

an ordered factor: the age of the insured in 4 groups labelled <25, 25–29, 30–35, >35.
Holders

numbers of policyholders.
Claims

numbers of claims
Source
L. A. Baxter, S. M. Coutts and G. A. F. Ross (1980) Applications of linear models in motor insurance. Proceedings of the 21st International Congress of Actuaries, Zurich pp. 11–29.
M. Aitkin, D. Anderson, B. Francis and J. Hinde (1989) Statistical Modelling in GLIM. Oxford University Press.
References
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with SPLUS. Fourth Edition. Springer.
Examples
## maineffects fit as Poisson GLM with offset
glm(Claims ~ District + Group + Age + offset(log(Holders)),
data = Insurance, family = poisson)
# same via loglm
loglm(Claims ~ District + Group + Age + offset(log(Holders)),
data = Insurance)