[R-sig-ME] Structural zeros in lme4

Lydia Belton lbelton at zoology.up.ac.za
Wed Oct 6 15:13:48 CEST 2010

Dear R users,

Thanks for the suggestions on how to work around this. One thing is, I
have got the impression from reading Agretsi that structural zeros need 
to be 'treated differently' to sampling zeros. I have an example of a glm
with a poisson distribution that subsets the data to remove the structural
zero combinations between between two fixed effects whilst leaving the
sampling zeros in place. However this isn't for interactions.

Unfortunately I'm not a statistician and I'm new to using R. Is this
something that I would also have to try to take into account or I have
tied myself in knots due to my extremely limited knowledge? Incidently I
don't actually have any sampling zeros in my data set if that makes a

Thank you all for your help it's very much appreciated


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