Demeaning and inclusion of interaction terms?

[Dankner, Nathan (NIH/NIMH) [F]]

Hello all,

I am attempting to run a repeated measures ANCOVA with age as a covariate, and I have a couple of questions regarding the ANCOVA model.  First of all, by default does SPSS demean/mean center the covariate (age)?  Also, does SPSS use the interaction terms and main effects in its ANCOVA model?  Thanks,

Nathan

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[Bruce Weaver]

See the article by  Van Breukelen et al.

   http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=1296348

Dankner, Nathan (NIH/NIMH) [F] wrote

Hello all,

I am attempting to run a repeated measures ANCOVA with age as a covariate, and I have a couple of questions regarding the ANCOVA model.  First of all, by default does SPSS demean/mean center the covariate (age)?  Also, does SPSS use the interaction terms and main effects in its ANCOVA model?  Thanks,

Nathan

=====================
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