Hey,

Thank you Ben for your message. Well, I feel a bit silly because I was 
already pointed that possibility but the advice got stuck somewhere I 
couldn't reach it...
I won't forget it this time !

Best regards

Alex


  On 31/03/2011 15:13, Ben Bolker wrote:
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> On 11-03-31 03:05 AM, Alexandre Villers wrote:
>> Good morning,
>>
>> I'm trying to fit a very simple model: the proportion of occupied nest
>> boxes according to food availability on a time serie (37 years). The
>> problem is that the glm (binomial error family with logit  link)
>> presents a marked overdispersion ( ~ 24). Checking the residuals showed
>> me they are correlated with a lag of 3 years (preys have cyclic
>> population dynamic) and accounting for this temporal correlation will
>> certainly improve the model.
>> I know how to cope with this with glmmPQL (with a corARMA correlation
>> structure) but I "cheat" a bit given I don't really need random effect.
>>
>> Is there a way to specify such correlation structure with gee or geepack
>> ? Any link to a pdf or webpage explaining the "how to" would be
>> appreciated...
>    I don't know the answer to that question, but if the phase of the
> cycle is consistent through the whole time period you could add a
> sinusoidal component (with known phase and period) to the model ...
>
>    Ben Bolker
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