You can do a transformation on your Y, and than use the normal tools.
Using something like a median test is not advisable due to low power, and a
wilcox.test is considered a better choice (although the meaning is more
complex when observations are not symmetrically distributed).

If you wish to perform a one way anova, which is non parametric, you can
use:
?kruskal.test
And after that you can use the tools suggested here by David
Winsemius<http://r.789695.n4.nabble.com/template/NamlServlet.jtp?macro=user_nodes&user=4999>
:
http://r.789695.n4.nabble.com/post-hoc-test-with-kruskal-test-td898661.html

With regards,
Tal



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----------------------------------------------------------------------------------------------




On Thu, Jul 19, 2012 at 11:14 PM, Data Analytics Corp. <
walt@dataanalyticscorp.com> wrote:

> Hi,
>
> A client has a consumption measure on each of four products.  The sample
> size is 75.  The consumption distributions are highly skewed for each
> product.  He would like a pairwise comparison test of the products, much
> like Tukey's HSD but using medians rather than means.  Is there such a
> median comparison test in R?
>
> Thanks,
>
> Walt
>
> ________________________
>
> Walter R. Paczkowski, Ph.D.
> Data Analytics Corp.
> 44 Hamilton Lane
> Plainsboro, NJ 08536
> ________________________
> (V) 609-936-8999
> (F) 609-936-3733
> walt@dataanalyticscorp.com
> www.dataanalyticscorp.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.
>

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