[R] Nonparametric generalization of ANOVA

[Ravi Varadhan]

David,

I agree with your sentiments.  I also think that it is bad posting etiquette not to sign one's genuine name and affiliation when asking for help, which "blue sky" seems to do a lot.  Bert Gunter has already raised this issue, and I completely agree with him. I would also like to urge the R-gurus to ignore such postings.

Best,
Ravi.
____________________________________________________________________

Ravi Varadhan, Ph.D.
Assistant Professor,
Division of Geriatric Medicine and Gerontology
School of Medicine
Johns Hopkins University

Ph. (410) 502-2619
email: rvaradhan at jhmi.edu


----- Original Message -----
From: David Winsemius <dwinsemius at comcast.net>
Date: Friday, March 5, 2010 9:25 am
Subject: Re: [R] Nonparametric generalization of ANOVA
To: blue sky <bluesky315 at gmail.com>
Cc: r-help at stat.math.ethz.ch


>  On Mar 5, 2010, at 8:19 AM, blue sky wrote:
>  
>  > My interpretation of the relation between 1-way ANOVA and Wilcoxon's
>  > test (wilcox.test() in R) is the following.
>  >
>  > 1-way ANOVA is to test if two or multiple distributions are the same,
>  > assuming all the distributions are normal and have equal variances.
>  > Wilcoxon's test is to test two distributions are the same without
>  > assuming what their distributions are.
>  >
>  > In this sense, I'm wondering what is the generalization of Wilcoxon's
>  > test to more than two distributions. And, more general, what is the
>  > generalization of Wilcoxon's test to multi-way ANOVA with arbitrary
>  > complex model formula? What are the equivalent F statistics and t
>  > statistics in the generalization of Wilcoxon's test?
>  >
>  > Note that I'm not interested in looking for a specific nonparametric
>  > test for a particular dataset right now, although this is important 
> in
>  > practice. What I'm interested the general nonparametric statistical
>  > framework that parallels ANOVA. Could somebody give some hints on what
>  > references I should look for? I have google searched this topic, but
>  > don't find a page that exactly answered my question.
>  
>  This is your first of three postings in the last hour and they are 
> all  
>  in a category that could well be described as requests for tutoring 
> in  
>  basic statistical topics. I am of the impression you have been  
>  requested not to engage in such behavior on this list. For this  
>  question for instance there is an entire CRAN Task View available and 
>  
>  you have been in particular asked to sue such resource before posting.
>  
>  It's not the described role of the r-help list to remediate your lack 
>  
>  of statistical background, but rather to deal with difficulties in  
>  applying the R-language to particular, discrete and exemplified  
>  problems.
>  
>  -- 
>  
>  David Winsemius, MD
>  West Hartford, CT
>  
>  ______________________________________________
>  R-help at r-project.org mailing list
>  
>  PLEASE do read the posting guide 
>  and provide commented, minimal, self-contained, reproducible code.