[R] Is there a non-parametric repeated-measures Anova in R ?

[Bert Gunter]

Frank:

See section 9.2. "Efficiency and it's Deficiencies" of Cuthbert Daniel's
"Application of Statistics to Industrial Experimentation" (1976, Wiley --
alas, probably now out of print).

Admittedly a different context, but statistical efficiency (aka "power") is
not a transcendent virtue. Robustness (in various manifestations) counts
also. Remember also that in reality, P values are typically biased low due
to lack of independence: experimenter almost never randomize; studies are
conducted in "convenience" order (often by necessity). Methodology that is
less sensitive to this, perhaps sacrificing an illusory power, may be
preferable.

I do not claim anything about what's better in the current case. I just wish
to caution against excessive religious orthodoxy.

Cheers,
Bert

Bert Gunter
Nonclinical Biostatistics
467-7374

http://devo.gene.com/groups/devo/depts/ncb/home.shtml

 

 


-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On
Behalf Of Frank E Harrell Jr
Sent: Wednesday, June 16, 2010 11:31 AM
To: r-help at r-project.org
Subject: Re: [R] Is there a non-parametric repeated-measures Anova in R ?

The Friedman test lacks power.  When there are only 2 blocks it reduces 
to the inefficient sign test.

Frank

On 06/16/2010 12:43 PM, Tal Galili wrote:
> Hello Jeremy,
> Thank you for replying.
>
> I came across friedman test (I even wrote and published R code to easily
> perform a post-hoc analysis of friedman
>
test<http://www.r-statistics.com/2010/02/post-hoc-analysis-for-friedmans-tes
t-r-code/>
> ).
> But what I am after is *multi-way* repeated-measures anova.  Thank you for
> your reply which allowed me to clarify my intentions.
>
> Best,
> Tal
>
>
>
>
> ----------------Contact
> Details:-------------------------------------------------------
> Contact me: Tal.Galili at gmail.com |  972-52-7275845
> Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) |
> www.r-statistics.com (English)
>
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>
>
>
>
> On Wed, Jun 16, 2010 at 8:30 PM, Jeremy
Miles<jeremy.miles at gmail.com>wrote:
>
>> It's possible to use the ordinal regression model if your data are
>> ordered categories.  The standard non-parametric test is the Friedman
>> test.
>>
>> ?friedman.test
>>
>> Jeremy
>>
>>
>> On 16 June 2010 10:22, Tal Galili<tal.galili at gmail.com>  wrote:
>>> Hello Prof. Harrell and dear R-help mailing list,
>>>
>>> I wish to perform a non-parametric repeated measures anova.
>>>
>>> If what I read online is true, this could be achieved using a mixed
>> Ordinal
>>> Regression model (a.k.a: Proportional Odds Model).
>>> I found two packages that seems relevant, but couldn't find any vignette
>> on
>>> the subject:
>>> http://cran.r-project.org/web/packages/repolr/
>>> http://cran.r-project.org/web/packages/ordinal/
>>>
>>> So being new to the subject matter, I was hoping for some directions
from
>>> people here.
>>>
>>> Are there any tutorials/suggested-reading on the subject?  Even better,
>> can
>>> someone suggest a simple example code for how to run and analyse this in
>> R
>>> (e.g: "non-parametric repeated measures anova") ?
>>>
>>> I waited a week to repost this question.  If I should have waited
longer,
>> or
>>> not repost this at all - then I am truly sorry.
>>>
>>> Thanks for any help,
>>> Tal
>>>
>>>
>>>
>>>
>>>
>>>>
>>>> ----------------Contact
>>>> Details:-------------------------------------------------------
>>>> Contact me: Tal.Galili at gmail.com |  972-52-7275845
>>>> Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew)
>> |
>>>> www.r-statistics.com (English)
>>>>
>>>>
>>
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>>>>
>>>>
>>>>
>>>
>>>         [[alternative HTML version deleted]]
>>>
>>> ______________________________________________
>>> R-help at 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.
>>>
>>
>>
>>
>> --
>> Jeremy Miles
>> Psychology Research Methods Wiki: www.researchmethodsinpsychology.com
>>
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
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> PLEASE do read the posting guide
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>


-- 
Frank E Harrell Jr   Professor and Chairman        School of Medicine
                      Department of Biostatistics   Vanderbilt University

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