[R] Multivariate Transformations

[Gavin Simpson]

On Wed, 2009-05-27 at 08:39 -0400, stephen sefick wrote:
> It depends on what you are after.  I am by no means a wunderkind when
> it comes to transformation, but in the package vegan type
> ?wisconsin
> and that should give you a start,  but if you know what
> transformations you would like to preform then apply should do what
> you need with whatever transformation you are trying to use.

decostand provides (mostly) standardisations not transformations, it
even says so. What Holger is looking for is something like a Box Cox
transform for bivariate normality but to instead achieve multivariate
normality. That is a different kettle of fish to what decostand tries to
do.

HTH

G

> 
> Stephen Sefick
> 
> On Wed, May 27, 2009 at 5:26 AM, Hollix <Holger.steinmetz at web.de> wrote:
> >
> > Hello folks,
> >
> > many multivariate anayses (e.g., structural equation modeling) require
> > multivariate normal distributions.
> > Real data, however, most often significantly depart from the multinormal
> > distribution. Some researchers (e.g., Yuan et al., 2000) have proposed a
> > multivariate transformation of the variables.
> >
> > Can you tell me, if and how such a transformation can be handeled in R?
> >
> > Thanks in advance.
> > With best regards
> > Holger
> >
> >
> > ---------------
> > Yuan, K.-H., Chan, W., & Bentler, P. M. (2000). Robust transformation with
> > applications to structural equation modeling. British Journal of
> > Mathematical and Statistical Psychology, 53, 31–50.
> > --
> > View this message in context: http://www.nabble.com/Multivariate-Transformations-tp23739013p23739013.html
> > Sent from the R help mailing list archive at Nabble.com.
> >
> > ______________________________________________
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> > and provide commented, minimal, self-contained, reproducible code.
> >
> 
> 
> 
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