Thanks Daniel
So I guess the best is to drop one of the collinear variables.?
Colin ________________________________________
From: owner-statalist@hsphsun2.harvard.edu [owner-statalist@hsphsun2.harvard.edu] on behalf of daniel klein [klein.daniel.81@googlemail.com]
Sent: 29 July 2011 11:01 AM
To: statalist@hsphsun2.harvard.edu
Subject: Re: st: fixed effects with multicollinearity
Colin,
please note that mean centring does nothing to solve the underlying
problem of collinarity (if there is something like that)., see e.g.
Echambadi and Hess (2007) or Shieh, G. (2011).
However, in another post
(http://www.stata.com/statalist/archive/2011-04/msg01204.html) Maarten
Buis pointed out that in the special case, where a variable is
interacted with itself, to model non-linearities, centering can help.
Echambadi and Hess (2007). Mean-Centering Does Not Alleviate
Collinearity Problems in Moderated Multiple Regression Models.
Marketing Science, 26: 438-445
Shieh, G. (2011). Clarifying the role of mean centring in
multicollinearity of interaction effects. British Journal of
Mathematical and Statistical Psychology, 64: 1-12
Best
Daniel
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
________________________________
This email and all contents are subject to the following disclaimer:
http://disclaimer.uj.ac.za
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
