Number of prostate cancer deaths and midperiod population for nonwhites in the USA by age and period.
The cohort index k is related to age and period indices (i and j, respectively) by k = j + I - i,
where I = max(i) (Holford, 1983, Table 2).
Usage
data(cohorts)
Format
A data frame with 49 observations on the following 4 variables.
period
A factor with levels 1935-, 1940-, ..., 1965-.
age
A factor with levels 50-, 55-, ..., 80-.
y
Numeric: the number of prostate cancer deaths.
n
Numeric: the midperiod population size.
References
Holford, T.R., 1983. The estimation of age, period and cohort effects for vital rates. Biometrics 39, 311-324.