[R] Problems with lme random slope+intercept model

[Ben Bolker]

anord <andreas.nord <at> zooekol.lu.se> writes:

> 
> Dear all, 
> I'm trying to fit a model on ecological data in which I have measured a few
> biotic and abiotic factors over the course of a few days in several
> individuals. Specifically, I'm interested in modelling y ~ x1, with x2, x3,
> and 'factor' as independent variables. Because data suggests both slope and
> intercept (for y ~x1) might differ between individuals, I'd want to compare
> model fit for a saturated model  with random intercept only, against
> that of
> a model with random slope + intercept. Data are available in
>  full from this
> link: 
> https://www.dropbox.com/s/mzk8utvgkzp4rtr/data.txt

  Sorry for snipping context, and for not really responding, but this
question might get more traction on the r-sig-mixed-models mailing list
(r-sig-mixed-models at r-project.org) ...
  I would guess that your model is overfitted/unidentifiable, but I would
have to look a lot more carefully to know for sure.

  Ben Bolker