[R] Error message

Havenga, BS, Mnr <15264831@sun.ac.za>
Tue, 30 Apr 2013 11:45:26 -0000

Hi there

I am a Masters student at the University of Stellenbosch. I have been using R to
analyze the data, using the GLS model, of one of my experiments.
The problem that I am having is that whenever I run my model using:
fit.glsmodel1<-gls(Number~as.factor(Season)+as.factor(Depth)+as.factor(Orientation),
data=Number, weights=varPower(), method="ML")

I get the error:
Error in glsEstimate(object, control = control) :    computed "gls"
fit is singular, rank 8

I would like to know if anyone can tell me what is causing this error. Any
advice will be much appreciated.

Kind regards
Brendan

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