[R-sig-ME] Mixed modelling and Species Area Relationship (SAR)

[Thierry Onkelinx]

Dear Gitu,

If the area is constant within each method, then the random effect of
method will model the area effect. If not you can add area to the fixed
effects of the model. You have several options: as an offset, as a
(log)linear trend, as a smoother, ... Much will depend on your assumption
on the relation between species richness and sample area.

Best regards,

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

To call in the statistician after the experiment is done may be no more
than asking him to perform a post-mortem examination: he may be able to say
what the experiment died of. ~ Sir Ronald Aylmer Fisher
The plural of anecdote is not data. ~ Roger Brinner
The combination of some data and an aching desire for an answer does not
ensure that a reasonable answer can be extracted from a given body of data.
~ John Tukey

2015-11-26 15:09 GMT+01:00 Gitu wa Mbui <gitumbui op gmail.com>:

> How does one account for the species area relationship in a mixed model of
> predicting species richness?
>
> Sampling was carried out using different methods - photoquadrats, transects
> etc ( five different methods).
>
> The area of the sampled plots differed and there were hundreds of plots. I
> am constructing a glmm for predicting the species richness, overall, and
> have configured the Method of sampling as a random intercept in the model.
> I am wondering how I should construct the model such the influence of SAR
> is taken into account - considering that SAR can not be a random factor.
>
> ~Gitu
>
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