[R] Ordinal mixed model

[David Atkins]

Patrick--

One other option in addition to Thierry's suggestion, within R you might 
also consider the ordinal package, which handles random-intercept models.

That said, if you are used to SPSS, I suspect this will be a titanic 
pain trying to move to R (part. if just for this one analysis...). 
Having been taught SPSS in grad school (and still working amongst many 
SPSS users), the two programs are very different.

SPSS will fit GEE models, which I would guess is a defensible approach 
for your data (given the very little that I know about it...).  You 
might explore that before scaling the steep learning curve of R.

Hope that helps.

cheers, Dave


Dear Patrick,

You can fit such a model with the MCMCglmm package. Have a look at the 
vignette of that package.

install.packages("MCMCglmm")
vignette("CourseNotes", package = "MCMCglmm")

But I'm affraid that this will require some rockclimbing upon the 
learning curve if you are a R novice.

HTH,

Thierry

----------------------------------------------------------------------------
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek
team Biometrie & Kwaliteitszorg
Gaverstraat 4
9500 Geraardsbergen
Belgium

Research Institute for Nature and Forest
team Biometrics & Quality Assurance
Gaverstraat 4
9500 Geraardsbergen
Belgium

tel. + 32 54/436 185
Thierry.Onkelinx op inbo.be
www.inbo.be

To call in the statistician after the experiment is done may be no more 
than asking him to perform a post-mortem examination: he may be able to 
say what the experiment died of.
~ Sir Ronald Aylmer Fisher

The plural of anecdote is not data.
~ Roger Brinner

The combination of some data and an aching desire for an answer does not 
ensure that a reasonable answer can be extracted from a given body of data.
~ John Tukey


 > -----Oorspronkelijk bericht-----
 > Van: r-help-bounces op r-project.org
 > [mailto:r-help-bounces op r-project.org] Namens Patrick Walsh
 > Verzonden: woensdag 22 september 2010 18:29
 > Aan: r-help op r-project.org
 > Onderwerp: [R] Ordinal mixed model
 >
 > Hello,
 > I am trying to build a generalised linear mixed model.  My
 > dependent variable is ordinal.  I have a random factor (7
 > individuals), and a repeated measure where the dependent
 > variable was measured three times for each of four attempts
 > (so the repeats are nested).  I also have a few covariates.
 > I am a complete novice in R, being used to using SPSS.  SPSS
 > lets me build an ordinal model with repeated measures, but
 > can't include a random factor.  So that is really the hurdle,
 > is this possible in R.  And is there a way to do this that
 > could be explained to someone who has no experience in R?
 > Any help would be greatly appreciated.
 > Kind Regards,
 > ptwal
 >
 >
 >
 >
 > ______________________________________________
 > R-help op 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.
 >

-- 
Dave Atkins, PhD
Research Associate Professor
Department of Psychiatry and Behavioral Science
University of Washington
datkins at u.washington.edu

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