hi all,
Using the nlme package, I am doing some lme analyses on the effect of  
introduced fish on zooplankton biodiversity in alpine lakes.
Everything going fine with all zooplankton taxa analyzed so far but  
one for which I get an error message which I do not know how to  
interpret:

 > zoop.lme<-lme(Logcrpic ~ as.factor(year)+as.factor(month) + FAC1 +  
FAC2 + FAC3 + as.factor(fish),random=~1| 
Cod,data=zooplankton,na.action=na.omit)

Error in solve.default(estimates[dimE[1] - (p:1), dimE[2] - (p:1),  
drop = FALSE]) :
	system is computationally singular: reciprocal condition number =  
2.21155e-16

I would be thankful to anybody who could assist me in understanding  
what is going wrong with this particular variable...

best regards,
Achaz

Dr. Achaz von Hardenberg
------------------------------------------------------------------------ 
--------------------------------
Centro Studi Fauna Alpina - Alpine Wildlife Research Centre
Servizio Sanitario e della Ricerca Scientifica
Parco Nazionale Gran Paradiso, Degioz, 11, 11010-Valsavarenche (Ao),  
Italy




	[[alternative HTML version deleted]]


