[R] mvabund package: errors using manyglm() and meanvar.plot()

Dear R users, I am trying to analyze multivariate abundance data using the mvabund package, but errors occur for several functions. I created a mvabund object named faunadat consisting of 8 dependent variables each containing 64 positive integer values (bact, fung, plant, omn, pred, orib, meso, s

[R] p-value for fixed effect in generalized linear mixed model

mmix, corrected for overdispersion with "random _residual_", it also gives a p-value for "spikes" of 0,985. So if "spikes" is not having a significant effect on "aphids", then why the above mentionned p-value generated by anova in R? Can anyone expla

[R] Cholmod error `matrix not positive definite'

give any problem when I build the exact same models in SAS with proc glimmix... Does someone have experience with this type of problem? Thank you in advance, Martijn. -- Martijn Vandegehuchte Ghent University Department Biology Terrestrial Ecology Unit K.L.Ledeganckstraat 35 B-9000 Ghent