[R] overdispersion + GAM

Gavin Simpson gavin.simpson at ucl.ac.uk
Mon Feb 11 18:36:43 CET 2008


On Mon, 2008-02-11 at 07:35 -0800, anna banana wrote:
> Hi,
> 
> there are a lot of messages dealing with overdispersion, but I couldn't find
> anything about how to test for overdispersion. I applied a GAM with binomial
> distribution on my presence/absence data, and would like to check for
> overdispersion. Does anyone know the command?

Bernoulli data (presence/absence of single species say) can't be
overdispersed, so there is no need to test or correct for it.

G

> 
> Many thanks,
> 
> Anna
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