The rain data has 366 real valued binomial responses
representing days on which it rained over the course of two years in
Tokyo.
A list with three components: y, the repsonse representing
the number of times it has rained on the ith day of the year in
Tokyo from 1983 through 1984, X, a matrix of ones, and
n, the number of observations for each day. n is two
for all days except Feb. 29.
This is the famous Tokyo rainfall data from Kitagawa (1987).
Genshiro Kitagawa. Non-Gaussian State-Space Modeling of Non-stationary Time Series. Journal of the American Statistical Association (1987).