library(poliscidata)
# Collapsing numeric variables into substantively useful categories
describe(gss$age, weights=gss$wtss)
gss$age7 = cut2(gss$age, c(21, 31, 41, 51, 61, 71, 89))
levels(gss$age7) = c("18-20", "21-30", "31-40", "41-50", "51-60", "61-70", "71-")
gss$age7 = as.ordered(gss$age7)
# the next two lines not strictly necessary but should check our work
levels(gss$age7)
freq(gss$age7, gss$wtss, plot=F)