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Re: st: how to get the components variable after -pca- or -fa-?
From
Nick Cox <[email protected]>
To
[email protected]
Subject
Re: st: how to get the components variable after -pca- or -fa-?
Date
Tue, 3 Apr 2012 16:43:29 +0100
You do not spell out the precise commands you used for -pca- or -fa-,
although you went for factor analysis, it seems. But remember that by
default the variables must be standardised first to mean 0 and
variance 1. It doesn't seem that you did that.
Nick
2012/4/3 Grace Jessie <[email protected]>:
> Could anyone tell me how to get the components variable after -pca- or -fa-?
> I know -predict f1- works well for the first component. However, I want to know how to calculate it? In my mind, it should equal each variable multiplied by its score. Disppointedly, it does not. Could anyone explain to me?
> for example,
> predict p1
> (regression scoring assumed)
> Scoring coefficients (method = regression)
> ------------------------
> Variable | Factor1
> -------------+----------
> dv21 | 0.28335
> dv22 | 0.28218
> dv23 | 0.28129
> dv24 | 0.27461
> ------------------------
> So P1=0.28335*dv21+0.28218*dv22+0.28129*dv23+0.27461*dv24? Why not?
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