[R] Displaying Compositional Data With 46 Parts

[Rich Shepard]

On Fri, 17 Jul 2015, Bert Gunter wrote:

> I believe John Aitchison's book and papers are the authoritative basic
> resources. Have you read them?

Bert,

   Yes, I have.

> The problem is that the support of the distributions are (hyper)simplexes,
> not Euclidean space, due to the requirement that the proportions must sum
> to 1. This means that complicated animals like Dirichelet distributions
> must be used to model populations, and the sampling theory is therefore
> specialized. It's difficult for most folks to get their heads around this.

   That's true, When I read the math I move my lips and follow along with a
finger. :-)

   My question is focused on presentation of graphic presentation of the
data, such as a matrix of ternary diagrams that show the distribution of the
response variables to the explanatory variables. The analysis of benthic
macroinvertebrate functional feeding groups has 5 response variables which
resulted in a 5-by-5 ternary diagram matrix. Anything larger than that would
require the eyesight of a teenager to see any details.

   I'll keep searching the literature for a suitable example. Perhaps a CoDA
SIG will develop on within the R mail list ecosystem in the not-too-distant
future.

Thanks,

Rich