Hi all,
I am trying to get the seasonal estimates of the breeding population (% of the breeding population in a concrete period) from diverse Species in the different seasons of the year. To note that I have obtained this data from diferent longitudinal studies, having unbalanced data. So I am using:
Population to control the pseudoreplication
ID_study to control the different samplings,
Species (Genus*Family) to take into account the taxonomy
However, I would like to take into account the density using it as offset. The problem is that when I include this term in orocethe SAS code I get the following answer: "WARNING: Obtaining minimum variance quadratic unbiased estimates as starting values for the covariance parameters failed".
proc glimmix data=breeding method=laplace plots=(ResidualPanel(conditional marginal));
class Season Species Genus Family Population ID_study Month ;
model Breed_population = Season Month (Season)
/dist=beta offset=Density
ddfm=none covb s;
random intercept / subject = Population (ID_study);
random intercept / subject= Species (Genus*Family);
nloptions maxiter=150;
lsmeans Season/cl diff PLOT=diff (NOabs center) adjust=tukey;
lsmeans Season/cl ilink;
run;
Anyone know how I can overcome this problem?
Thanks,
Rubén
The warning was due to the amount of decimals of the offset. When I reduce it to 2-3 decimals I could to carry out the model.
I hope it may help someone
Sorry for the inconvences!!!
The warning was due to the amount of decimals of the offset. When I reduce it to 2-3 decimals I could to carry out the model.
I hope it may help someone
Sorry for the inconvences!!!
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