In the fabric data (Bissell, 1972), the main response is the number of faults in a bolt of fabric of length.
data("fabric")
A data frame with 32 observations on the following 3 variables.
x
log of length
y
number of faults
rf
obervation number for 32 obervations
Bissell, A.F. (1972). A negative binomial model with varying element sizes. Biometrika, 59, 435--441.