[R] Regression Error: Otherwise good variable causes singularity. Why?

[asdir]

@JLucke:
As for the africa variable: I took it out of the model, so that we can
exclude this variable itself and collinearity between the africa and the
litrate variable as causes for the litrate-problem.  This also removed the
singularity remark at the top. However, the problem with litrate-variable
seen as many factors remains.

Just to clarify: The second results table is fictional to explain where I
was headed with my regression.

Anyway, thanks for the quick answer.

@David:
Thanks for the pointer. It was in fact a bad variable, but I created it
myself. I changed the set halfway in between my calculations and thought I
had adjusted everything. It turns out, that I forgot to adjust the
set-length which is re-set in between the two steps of my Heckman-procedure.
In any case: Thanks for the quick and helpful reply. :-)
-- 
View this message in context: http://r.789695.n4.nabble.com/Regression-Error-Otherwise-good-variable-causes-singularity-Why-tp2322780p2322925.html
Sent from the R help mailing list archive at Nabble.com.