[R-sig-eco] Multivariate Analyses of Ecological Communities

[Jari Oksanen]

On 04/11/2013, at 17:59 PM, Rich Shepard wrote:

>  I've read the docs for anosim, adonis, and mrpp and am currently reading
> the vegan tutorial. Toward the end of the anosim and mprr docs the author
> writes that each has potential shortcomings and recommends the adonis
> package be used instead. This leads to my two questions:
> 
>  1) Why are anosin and mrpp packages still maintained and included? That
> they are suggests question

To serve the people?

> 
>  2) Under what circumstances are these two packages appropriately used?
> 
I don't know, but since they are available, it is possible to find out.

I have suggested in the documentation that adonis() usually is better, but it also suffers from similar problems as these alternatives. My analysis suggests that adonis() is more robust and reliable. However, not everybody agrees, and alternatives are provided for these standard methods. Since the alternatives are provided, you can study the issue independently.

The existence of a method is not a sufficient reason to use that method.  

Cheers, Jari Oksanen