Florian, There are a number of different ways to handle data like this. Two that come to my mind are shown below. You could allow each observation to be represented by multiple rows in the data frame:
obs dishes 1 1 saucer 2 2 cup 3 2 plate 4 2 saucer 5 3 cup 6 3 plate 7 4 cup 8 4 saucer 9 6 plate 10 6 saucer 11 7 plate 12 8 cup Or you could let each level be its own variable: obs cup plate saucer 1 1 0 0 1 2 2 1 1 1 3 3 1 1 0 4 4 1 0 1 5 5 0 0 0 6 6 0 1 1 7 7 0 1 0 8 8 1 0 0 The arrangement that you choose will likely depend on what you want to do with the data. Jean Florian Ahrweiler <florian.ahrwei...@uni-wh.de> wrote on 11/15/2012 10:10:53 AM: > > In a data frame, I would like to assign two or more factors to one > observation. Is it possible? If so, how? > > Example: In the variable $ dishes, there are several levels: "cup", > "plate", "saucer". In my first observation, I see a saucer only. But in > the second one, I see a cup and a saucer. In the third, however, there > is only a cup, in the fourth a plate only and so forth. > > I'm an R beginner and I'll be grateful for any help. > > Florian [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list 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.