RE: st: correcting skewness of an indep variables

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- I wrote:
> > Another reason for skewness is the presence of a spike
> > --- that is, a single value that is very common. In
> > that case you could consider adding the variable
> > linearly + a dummy indicating whether or not an
> > observations belongs to the spike group or not. We
> > would do that, if think that that
 
--- On Mon, 15/3/10, Cohen, Elan wrote:
> Do you know of any references for this type of
> procedure?  

It is basically a generalization of what Allison (2002) 
discusses in footnote 5. Ironically, this footnote is 
there to indicate an exception to his rule that 
adding such dummies to control for missing is usually 
not wise...

For an example of what such an analysis might look 
like, see chapter 5 of my dissertation:
http://www.maartenbuis.nl/dissertation/

Hope this helps,
Maarten

Paul Allison (2002) Missing Data. Thousand Oaks: Sage
(I think, I left my copy at home)

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------





      

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