Dear All, I have a seemingly standard problem to which I somehow I do not find a simple solution. I have individual level data where x is a categorical variable with 3 categories which I would like to aggregate by age.
age x 45 1 45 2 46 1 47 3 47 3 and so on. It should after transformation look like that age x_1 x_2 x_3 45 1 0 1 46 1 0 0 47 0 0 2 Basically to calculate prevalences by age categories. Thanks for any pointers! Cheers! ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.