[R] post-hoc test with kruskal.test()

[Meyners, Michael, LAUSANNE, AppliedMathematics]

Robert,

you can do the corresponding paired comparisons using wilcox.test. As far as I know, there is no such general correction as Tukey's HSD for the Kruskal-Wallis-Test. However, if you have indeed only 3 groups (resulting in 3 paired comparisons), the intersection-union principle and the theory of closed test procedures should allow you to do these test without further correction, given the global test was statistically significant.

HTH, Michael



> -----Original Message-----
> From: r-help-bounces at r-project.org 
> [mailto:r-help-bounces at r-project.org] On Behalf Of Robert Kalicki
> Sent: Mittwoch, 14. Oktober 2009 09:17
> To: r-help at r-project.org
> Subject: [R] post-hoc test with kruskal.test()
> 
> Dear R users,
> 
> I would like to know if there is a way in R to execute a 
> post-hoc test (factor levels comparison, like Tukey for 
> ANOVA) of a non-parametric analysis of variance with 
> kruskal.test() function. I am comparing three different 
> groups. The preliminary analysis using the 
> kruskal-wallis-test show significance, but I still don't know 
> the relationship and the significance level between each group?
> 
>  
> 
> Do you have any suggestion?
> 
>  
> 
> Many thanks in advance!
> 
>  
> 
> Robert
> 
>  
> 
>  
> 
> ___________________________________________
> Robert M. Kalicki, MD
> 
> Postdoctoral Fellow
> 
> Department of Nephrology and Hypertension
> 
> Inselspital
> 
> University of Bern
> 
> Switzerland
> 
> 
> 
> Address:
> 
> Klinik und Poliklinik für Nephrologie und Hypertonie
> 
> KiKl G6
> 
> Freiburgstrasse 15
> 
> CH-3010 Inselspital Bern
> 
> 
> 
> Tel     +41(0)31 632 96 63
> 
> Fax    +41(0)31 632 14 58
> 
> 
> 
> 
> 	[[alternative HTML version deleted]]
> 
>