I have the results of a rating study in which ~30 participants rated a subset of 20 items on 25 different dimensions.
I would like to perform PCA on these ratings to reduce the 25 different dimensions. However, instead of doing this on the mean ratings for each item, I would like to perform the PCA at the level of individual ratings. I am assuming that in order to do this I have to specify the fact that ratings are nested within participants and within items (i.e., crossed random effects for subjects and items). Is this possible? -- Sent from: http://r.789695.n4.nabble.com/datatable-help-f2315188.html _______________________________________________ datatable-help mailing list datatable-help@lists.r-forge.r-project.org https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help
