[R] model non-integer count outcomes

[Thierry Onkelinx]

If you know the number of counts (n) used to calculate the average then you
can still use a poisson distribution.

Total = average * n
glm(total ~ offset(n), family = poisson)

​
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature and
Forest
team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance
Kliniekstraat 25
1070 Anderlecht
Belgium

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~ John Tukey
Op 22 jul. 2015 08:38 schreef "Don McKenzie" <dmck op u.washington.edu>:

> Or if there are enough averages of enough counts, the CLT provides another
> option.
>
> > On Jul 21, 2015, at 8:38 PM, David Winsemius <dwinsemius op comcast.net>
> wrote:
> >
> >
> > On Jul 21, 2015, at 8:21 PM, Wensui Liu wrote:
> >
> >> Dear Lister
> >> When the count outcomes are integers, we could use either Poisson or
> >> NB regression to model them. However, there are cases that the count
> >> outcomes are non-integers, e.g. average counts.
> >> I am wondering if it still makes sense to use Poisson or NB regression
> >> to model these non-integer outcomes.
> >
> > There is a quasi-binomial error model that accepts non-integer outcomes.
> >
> > --
> >
> > David Winsemius
> > Alameda, CA, USA
> >
> > ______________________________________________
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>
>
> ______________________________________________
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