Hello Mr. Burns, Hello Mr. Dwinseminus thank you very much for your incredible quick and efficient reply! I was completely successful with the following command:
pairs<-data.frame(pred=factor(unlist(input[,-c(1,ncol(input))])),ref=factor(input[,ncol(input)])) In case of the "input" example data.frame I sent with my question the above code is equivalent to: pairs<-data.frame(pred=factor(unlist(input[2:17])),ref=factor(input[,18])) Great! That is exactly what I was looking for! This simple code will save me hours! Patrick, your book looks in fact very interesting and will be my perfect reading material for the following nights :-) (probably not only the first chapter ;-). Thanks for the hint - and the free book of course. David, the "input" data.frame is the result of the reshape-command I performed. I just copied it from the R-console into the e-mail. In fact the first column "video" is not part of the data, but needed for analysis with kappam.fleiss function of the irr-package. Sorry, you are absolutely correct, I should have mentioned this in my question. I will improve when I ask my next question :-). Again I like to thank you for your help and wish you a pleasant Sunday. Greetings from Munich, Felix Patrick Burns wrote: > If I understand properly, you want > > input[, -c(1, ncol(input))] > > rather than > > input[[, -c(video, 21)]] > > Chapter 1 of S Poetry might be of interest to you. > > Patrick Burns > [EMAIL PROTECTED] > +44 (0)20 8525 0696 > http://www.burns-stat.com > (home of S Poetry and "A Guide for the Unwilling S User") > > drflxms wrote: >> Dear R-colleagues, >> >> another question from a newbie: I am creating a lot of simple >> pivot-charts from my raw data using the reshape-package. In these charts >> we have medical doctors judging videos in the columns and the videos >> they judge in the rows. Simple example of chart/data.frame "input" with >> two categories 1/0: >> >> video 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 >> >> 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >> 2 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 >> 3 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >> 4 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >> 5 5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 >> 6 6 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 >> 7 7 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >> 8 8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 >> 9 9 0 0 0 0 0 0 0 0 0 1 0 1 1 0 1 1 0 0 0 1 0 >> 10 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >> >> I recently learned, that I can easily create a confusion matrix out of >> this data using the following commands: >> >> pairs<-data.frame(pred=factor(unlist(input[2:21])),ref=factor(input[,22])) >> >> pred<-pairs$pred >> ref <- pairs$ref >> library (caret) >> confusionMatrix(pred, ref, positive=1) >> >> - where column 21 is the reference/goldstandard. >> >> My problem is now, that I analyse data.frames with an unknown count of >> columns. So to get rid of the first and last column for the "pred" >> variable and to select the last column for the "ref" variable, I have to >> look at the data.frame before doing the above commands to set the proper >> column numbers. >> >> It would be very comfortable, if I could address the last column not by >> number (where I have to count beforehand) but by a variable "last >> column". >> >> Probably there is a more easy solution for this problem using the names >> of the columns as well: the reference is always number "21" the first >> column is always called "video". So I tried: >> >> attach(input) >> pairs<-data.frame(pred=factor(unlist(input[[,-c(video,21)]])),ref=factor(input[[21]])) >> >> >> which does not work unfortunately :-(. >> >> I'd be very happy in case someone could help me out, cause I am really >> tired of counting - there are a lot of tables to analyse... >> >> Cheers and greetings from Munich, >> Felix >> >> ______________________________________________ >> 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. >> >> >> ______________________________________________ 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.