At 18:25 09/08/2004, I wrote:
I think what Cordula really wants might be centring, rather than scaling.
If you extract a constant X_0 from an X-variate before fitting the
regression model, and therefore regress Y with respect to X-X_0, then the
intercept will be the expected value of Y if X==X_0, instead of the
expected value of Y if X==0.
Sorry, "extract" should of course be "subtract" here.
Roger
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Roger Newson
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King's College London
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