[R] princomp and eigen
Rolf Turner
rolf.turner at xtra.co.nz
Mon May 16 10:48:53 CEST 2011
On 16/05/11 17:44, Ooi Wen Fong wrote:
> Hi.
> I was comparing the components from princomp's loadings and the eigen given
> the same input.
> I found that the sign of componenets (+/-) are opposite between the two
> components (from princmop and eigen) but the magnitudes are identical. Why?
[Why is the sky blue? Why are fire engines red? Why don't they teach
linear algebra these days?]
Because if A%*%x = lambda*x then
A%*%(-x) = lambda*(-x).
cheers,
Rolf Turner
P. S. Why is a duck? Answer: Because the higher you go, the
vest has no sleeves.
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