Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: st: Interpretation of Interaction terms in log-lin
From
[email protected] (Brendan Halpin)
To
[email protected]
Subject
Re: st: Interpretation of Interaction terms in log-lin
Date
Tue, 22 May 2012 11:41:52 +0100
On Tue, May 22 2012, Lukas Borkowski wrote:
> my simplified model can be written as y = ß0 + ß1x1 + ß2x2 + ß3x1_x2
> with the last expression being an interaction term.
>
> However, the dependent variable is in logs and the explanatory variables
> are not. I now wonder whether I have to add ß2 and ß3 before putting
> them into the e-function or to exponantiate each coeffecient seperately
> and then do the addition?
Not quite an answer but if you have a logged dependent variable this
piece by William Gould is very helpful:
http://blog.stata.com/tag/poisson-regression/
Towards an answer: I'd interpret the effect of the interaction the same
as in any other linear model, and deal with the relationship between the
(linear) predicted value and your original variable in a second step.
Brendan
--
Brendan Halpin, Department of Sociology, University of Limerick, Ireland
Tel: w +353-61-213147 f +353-61-202569 h +353-61-338562; Room F1-009 x 3147
mailto:[email protected] ULSociology on Facebook: http://on.fb.me/fjIK9t
http://teaching.sociology.ul.ie/bhalpin/wordpress twitter:@ULSociology
*
* 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/