[R-sig-eco] Re : Problem to use varpart

[Gavin Simpson]

On Thu, 2011-07-07 at 12:26 +0100, momadou sow wrote:
> Hi, 
> 
> Thank Gavin for your answer but for your request “but why would you
> want to?” : to partition the explained variance in my linear
> regression. Thus, I want have the contribution of each explanatory
> variable. 
> Momadou

Don't cherry-pick. What I actually said was why would you want to use
RDA to fit a linear model? Not why do you want to do variance
partitioning.

Anyway, as I said, you can't do what you want with varpart() so you need
to look at how you decompose a linear model (lm()).

G
> 
> De : Gavin Simpson <gavin.simpson at ucl.ac.uk>
> À : momadou sow <momadou at yahoo.fr>
> Cc : "R-sig-ecology at r-project.org" <R-sig-ecology at r-project.org>
> Envoyé le : Jeudi 7 Juillet 2011 23h00
> Objet : Re: [R-sig-eco] Problem to use varpart
> 
> On Thu, 2011-07-07 at 06:33 +0100, momadou sow wrote:
> > Hi, 
> > I did a linear regression with 5 explanatory variables. Now, to see
> the contribution of each variable, I use varpart  from vegan library.
> But varpart don’t accepts my 5 explanatory variables, it accept only
> 4. 
> > 1- How must I  do to use my 5 explanatory variables?
> > 2- Is it the sum of variance fraction of each variable must be equal
> to 1. 
> > Thanks for your help. 
> 
> varpart is for redundancy analysis - aka reduced rank regression. I
> suppose one can do linear regression with RDA, but why would you want
> to?
> 
> Anyway, you can't do what you want with varpart(). Look at
> interpretting
> the linear model directly.
> 
> G
> 
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> 
> 
> 

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 Dr. Gavin Simpson             [t] +44 (0)20 7679 0522
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