Thank you all very much for your very helpful and friendly comments! You have assured me that it?s a good thing spending the following days (or weeks?) by working me through the R-documentations. Some of you reminded me, that file-size might be important. Well, my file is not as big as several Million lines, just 500.000 cases x 200 variables (130 Megabytes) - and I think I won?t be using more than two variables at once. Bearing in mind your comments in the mailing list, my data shouldn?t be too large for R, as long as my computer doesn?t complain. It didn ?t complain using SPSS (except for exploratory analysis), so 128MByte RAM seem to be sufficient. Michael -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._