>> Hi Vincenzo,
>> 
>> Have a look at the mvabund package and the supporting papers - the manyglm function may be appropriate if you have count or PA data. This seems to me to be the most rigorous method. Those methods that use dissimilarity metrics to calculate ANOVA-like comparisons can tend to favour variables with high variance over those which are rare. This can lead to a lack of power to detect a difference between groups when it exists.
>> 
>> Hope that helps,
>> Liz

On 12/07/2012, at 8:30 AM, Vincenzo Ellis wrote:

> Dear all,
> 
> I'm used to comparing assemblages at different geographic locations using
> ordination techniques, where you have abundances or presence-absence of
> species and then look at how they separate in multivariate space.  I'm
> currently working with four sites/locations and want a more rigorous way to
> compare the species assemblages on them maybe using some king of ANOVA
> approach, but I'm not sure how to do it.  I've attached a subset of the
> data in case that makes providing suggestions easier.
> 
> Thank you so much!!
> 
> Vincenzo
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Liz Pryde
PhD Candidate (off-campus @ The University of Melbourne)
School of Earth and Environmental Sciences
James Cook University, QLD

elizabethpryde@gmail.com
epryde@unimelb.edu.au



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