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RE: st: manipulating matrix elements
The second paragraph applies when comparing
matrices with the same number of cells
(#rows * #cols). Varying matrix size would
mess up the correlation.
> -----Original Message-----
> From: Nick Cox
> Sent: 02 April 2006 17:25
> To: 'email@example.com'
> Subject: RE: st: manipulating matrix elements
> That's not quite my point.
> In one case, the standardization is additive
> and in the other it is multiplicative.
> Either should leave the two measures
> perfectly correlated, as a correlation is invariant
> under a linear transformation, such as conversion
> from Fahrenheit to Celsius or vice versa. I trust the
> failure to observe a correlation of 1
> is down to numerical fuzz.
> This still leaves the question of whether
> both standardizations are correct in different
> senses, or whether they are the same, but
> just appear superficially different.
> Otherwise put, suppose you are always
> right on something, but my numbers are always
> twice as big as yours. Our results
> are perfectly correlated but that doesn't
> affect the fact that I am biased and
> therefore wrong.
> Steve Vaisey
> > I compared the standardizations (yours and Martin's) on a
> > matrix of 11
> > variables (for a total of 55 non-redundant, 2 variable
> > They are highly correlated (~.99) so it's probably a matter
> > of taste at
> > one level. Or am I missing something?
> > Thanks again for your help on this.
> > Steve
> > >
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