[R] mixed model question and using lmer
Ben Bolker
bbolker at gmail.com
Thu Jun 2 04:35:21 CEST 2011
Wiggin <wiggin.peters <at> gmail.com> writes:
>
> i am analyzing some data and have a question i hope someone can
> answer.
>
> i want to use this sort of model:
>
[quoting snipped to fool gmane into letting me post a short answer]
lmer( y ~ x + (1 | ID ), family=binomial, weight=w)
so i want to explore the relationship between y and x, with a random
effect for each patient.
my question is this. is this a sensible model to use when the number
of observations for each patient ID is often one? I have 305
observations for 239 patients.186 of the patients have only one
observation each and another 40 have two observations each. at the
other extreme, one patient has 5 observations
lmer fits the model without complaining.
but is this a sensible thing to do? it might be silly if so many of
my patients only have on observation each. i've tried doing some
reading but i cannot find an answer to this question.
=========
This is really a better question for r-sig-mixed-models.
Please repost there.
The short answer that this is indeed sensible.
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