[R-sig-eco] transformation of percent coverage data in community analysis

[Rich Shepard]

On Tue, 17 Feb 2015, Marc Taylor wrote:

> A colleague of mine is doing some basic descriptive analyses of algal
> community data (e.g. MDS, PCA), and we got to talking about how his data
> (percent coverage) might be transformed before the calculation of distance
> matrices. This may be desirable in order to reduce the influence of
> dominant species in the analyses.

Marc,

   Consider Compositional Data Analysis with the packages compositions(),
robCompositions(), or zCompositions().

Rich