Re: [R] Wilcoxon test for mixed design (between-within subjects)
Hallo Christoph, > There is always the possibility to summarize the replicates and > then calculate a common pairwise Wilcoxon test. mmmh, in this case I prefer the Friedman test, I would like not to loose any data. > The Friedman test calculates the ranks inside of the blocks, for > each block separately and is not considering all subjects > jointly. true, but it considers all the treatments together, while Wilcoxon works per pairs of treatments within the blocks. > In R implemented is the case with unreplicated blocked data, so > this doesn't help you. > > > If no such method exists in R, I am anyway intersted in possible > > references. > > Look at: > > Myles Hollander & Douglas A. Wolfe (1999), _Nonparametric > statistical methods_. New York: John Wiley & Sons. > > There you find the generalization of the replicated case, but > you have to implement it. I already implemented the Friedman test for the replicated case although taken from Conover 1999 _Practical non parametric statistics_. I hope it is the same. My interest in a Wilcoxon procedure is due to the fact that according to Hsu 1996 _Multiple comparisons_ the Friedman test is not recommended for multiple comparisons becasue it has been shown that it is not a confident method (the actual alpha value is greater). Regards, Marco --- Marco Chiarandini, Fachgebiet Intellektik, Fachbereich Informatik, Technische Universität Darmstadt, Hochschulstraße 10, D-64289 Darmstadt - Germany, Office: S2/02 Raum E312 Tel: +49.(0)6151.166802 Fax: +49.(0)6151.165326 email: [EMAIL PROTECTED] web page: http://www.intellektik.informatik.tu-darmstadt.de/~machud __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] Wilcoxon test for mixed design (between-within subjects)
Hallo Marco Marco Chiarandini writes: > Hallo, > > is there any extension of the pairwise Wilcoxon test to a dependent > samples layout with replicates (or, in other terms, a one-way layout > with blocking and replicates)? > There is always the possibility to summarize the replicates and then calculate a common pairwise Wilcoxon test. > The Wilcoxon method with matched pairs works for the case of dependent > samples with one observation per block, while the Mann-Whitney test > works for independent samples, thus one single block and replicated > observations. Is there a method which mixes this two cases considering a > depedent sample design in which each block has more than one > observation? I know it exists a Friedman test for this case but in the > Friedman test ranks are constructed considering all subjects jointly, > while in Wilcoxon only the pair of subject currently considered are > ranked, thus resulting in a more powerful test. > The Friedman test calculates the ranks inside of the blocks, for each block separately and is not considering all subjects jointly. In R implemented is the case with unreplicated blocked data, so this doesn't help you. > If no such method exists in R, I am anyway intersted in possible > references. Look at: Myles Hollander & Douglas A. Wolfe (1999), _Nonparametric statistical methods_. New York: John Wiley & Sons. There you find the generalization of the replicated case, but you have to implement it. Regards, Christoph Buser -- Christoph Buser <[EMAIL PROTECTED]> Seminar fuer Statistik, LEO C11 ETH (Federal Inst. Technology) 8092 Zurich SWITZERLAND phone: x-41-1-632-5414 fax: 632-1228 http://stat.ethz.ch/~buser/ -- > Thank you for the consideration, > > Regards, > > Marco > > __ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
[R] Wilcoxon test for mixed design (between-within subjects)
Hallo, is there any extension of the pairwise Wilcoxon test to a dependent samples layout with replicates (or, in other terms, a one-way layout with blocking and replicates)? The Wilcoxon method with matched pairs works for the case of dependent samples with one observation per block, while the Mann-Whitney test works for independent samples, thus one single block and replicated observations. Is there a method which mixes this two cases considering a depedent sample design in which each block has more than one observation? I know it exists a Friedman test for this case but in the Friedman test ranks are constructed considering all subjects jointly, while in Wilcoxon only the pair of subject currently considered are ranked, thus resulting in a more powerful test. If no such method exists in R, I am anyway intersted in possible references. Thank you for the consideration, Regards, Marco __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
