The following post would not answer your question at full, but might give some good code/information: http://www.r-statistics.com/2010/02/post-hoc-analysis-for-friedmans-test-r-code/
----------------Contact Details:------------------------------------------------------- Contact me: tal.gal...@gmail.com | 972-52-7275845 Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) | www.r-statistics.com (English) ---------------------------------------------------------------------------------------------- On Sun, Feb 19, 2012 at 8:25 PM, <saschav...@gmail.com> wrote: > Some attribute x from 17 individuals was recorded repeatedly on 6 time > points using a Likert scale with 7 distractors. Which statistical test(s) > can I apply to check whether the changes along the 6 time points were > significant? > > set.seed( 123 ) > x <- matrix( sample( 1:7, 17*6, repl=T ), > nrow = 17, byrow = TRUE, > dimnames = list(1:17, paste( 'T', 1:6, sep='' )) > ) > > I found the Friedman test and the Quade test for testing the overall > hypothesis. > > friedman.test( x ) > quade.test( x ) > > However, the R help files, my text books (Bortz, Lienert and Boehnke, > 2008; Köhler, Schachtel and Voleske, 2007; both German), and the Wikipedia > texts differ in what they propose as requirements for the tests. R says > that data need to be unreplicated. I read 'unreplicated' as 'not-repeated', > but is that right? If so, the example, in contrast, in friedman.test() > appears to use indeed repeated measures. Yet, Wikipedia says the contrary > that is to say the test is good especially if data represents repeated > measures. The text books say either (in the same paragraph, which is very > confusing). What is right? > > In addition, what would be an appropriate test for post-hoc single > comparisons for the indication which column differs from others > significantly? > > Bortz, Lienert, Boehnke (2008). Verteilungsfreie Methoden in der > Biostatistik. Berlin: Springer > Köhler, Schachtel, Voleske (2007). Biostatistik: Eine Einführung für > Biologen und Agrarwissenschaftler. Berlin: Springer > > -- > Sascha Vieweg, saschav...@gmail.com > > ______________________________**________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/**listinfo/r-help<https://stat.ethz.ch/mailman/listinfo/r-help> > PLEASE do read the posting guide http://www.R-project.org/** > posting-guide.html <http://www.R-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. > [[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.
