Hi Travis,
I don't think that a p-value is going to tell you if there is a
biological meaningful difference between community.
What will be the metrics that you are planning to use with ANOSIM ?
Without seeing the data I can tell you that there is a difference
between communities, but the important question is how different they
are, so you can assess a practical or biological significance and a
p-value is not going to tell you that.
Best,
Manuel
On 28/03/2011 07:14 a.m., T. Travis Brown wrote:
Hello, I am trying to determine the best way to test for a difference in the overall
mussel community found in a stream between 1980 and 2008. I have seven sites with
presence/absence data. In addition to various descriptive statistics and graphs
(nonmetric multidimensional scaling) I would like to use ANOSIM because it offers a
P-value, and answers the question: "well, is there a difference or not?". I am
not as up-to-date on this literature as I would like to be. Does anyone know if this is
still an accepted test? Would some type of multi-response permutation procedure be
better?
T. Travis Brown
[email protected]
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*Manuel Spínola, Ph.D.*
Instituto Internacional en Conservación y Manejo de Vida Silvestre
Universidad Nacional
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