hello,
I have this warning. How can I resolve the problem?
WARNING: The covariance across equations (the S matrix) is singular. A generalized inverse was
computed by setting to zero the part of the S matrix for the following 9 equations
whose residuals are linearly dependent with residuals from earlier equations: aone atwo
athree afour afive asix anine aten power
Not sure, what type of analysis is this, but most likely this is a problem of multicollinearity.
It is exact collinearity, in that one of the variables is a linear combination of some the others. That is why a generalized inverse is used. You have two choices--accept the GI approach (my preference) or reparameterize your model.
Steve Denham
Hi Steve,
I also got a similar message as the other member (SASPHD) above.
Can you kindly provide a syntax on how to correct for singularity using the IV approach in a source-differentiated AIDS model?
Thanks.
Patrick
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