Re: Box's test warning

Posted by David Marso on Jun 13, 2013; 7:10pm
URL: http://spssx-discussion.165.s1.nabble.com/Box-s-test-warning-tp5720700p5720701.html

Maybe a more detailed data description?
Actual SYNTAX!
Sample sizes? Covariance matrices for each group.
etc etc...
Since this is a DATA DEPENDENT issue, you must be more forthcoming about the specifics.
Do you have an adviser overseeing the project?  
Maybe that person should sit down with you and help nail the issue?
This could be as simple as the one or more of the dependent variables being linearly related within one or both of the groups.  This would certainly be the case if one of the groups has fewer than 6 observations.

The Burl wrote

Hello,

I'm neck-deep in dissertation data analysis and can't get Box's to run for my MANCOVA. I get this warning in the output:
Warnings
Box's Test of Equality of Covariance Matrices is not computed because there are fewer than two nonsingular cell covariance matrices.

Here's how I set up my data:
looking at 2 groups
6 DVs
1 fixed factor (IV) at 2 levels. (this may be my problem...) Isn't this fixed factor essentially just set up as a grouping variable?? So I have 1's for one group and 2's denoting the second group...
My fixed factor is set up as "nominal" and my DVs are "Scale"

Please help!
Thanks in advance!
-Jon