[R] why scores are different in rda() and princomp()

[Gavin Simpson]

On Thu, 2010-01-21 at 21:56 +0800, echo_july wrote:
> hello,
>    I am doing PCA in R using some habitat factors, and I used the
> function result1=rda() and result2=princomp(),then pick up scores of
> the result1 and result2 using scores(),but the scores are
> significantly different,i do not know the meaning of it.
>    Best wishes!

Because scores.rda allows for scaling of the scores to emphasise aspects
of the data whereas the default scores method (which you are using to
extract the loadings from princomp) doesn't.

Are they the same if you do:

result1 <- rda(....)
scores(result1, scaling = 0)

HTH

G

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