Hi Rich, you might be interested of http://www.compositionaldata.com/. They have a forum for CoDa related questions. There seems to be a new R-package for CoDa: zCompositions.
Cheers, Kari Lintulaakso University of Helsinki On Fri, Sep 26, 2014 at 1:00 PM, <[email protected]> wrote: > Send R-sig-ecology mailing list submissions to > [email protected] > > To subscribe or unsubscribe via the World Wide Web, visit > https://stat.ethz.ch/mailman/listinfo/r-sig-ecology > or, via email, send a message with subject or body 'help' to > [email protected] > > You can reach the person managing the list at > [email protected] > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of R-sig-ecology digest..." > > > Today's Topics: > > 1. Compositional Data Analysis: Simplex Scaling Function > Selection (Rich Shepard) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 25 Sep 2014 15:45:07 -0700 (PDT) > From: Rich Shepard <[email protected]> > To: [email protected] > Subject: [R-sig-eco] Compositional Data Analysis: Simplex Scaling > Function Selection > Message-ID: <alpine.LNX.2.11.1409251531180.12417@localhost> > Content-Type: TEXT/PLAIN; format=flowed; charset=US-ASCII > > The data sets to be analyzed are proportions based on counts. Each row > is > closed; the proportions total 1.00. I understand the need to transform the > raw data to a CoDA simplex, and my reading strongly suggests that the > isometric log ratio (ilr) function is the most appropriate for these data. > > In Boogaart and Delgado's "Analyzing Compositional Data With R", page 30 > describes the various available scaling functions. The advice needed is > which is most appropriate for my data sets: > 'aplus' -- Aichison (ratio) geometry in the real data space. > 'rcomp' -- Real (interval) compositional scale. > 'acomp' -- Aichison (ratio) compositional scale. > Or, one of the others. > > Reading several docs leaves me confused over which one should be used > for > both descriptive statistics and further analyses such as CCA, clustering, > or > time series. > > There is no statistics group on stackexchange.com and stackoverflow.com > is > for programming questions, not statistical questions. If there is a better > place for this question, please point me to it as there will be other CoDA > questions as the analyses proceed. > > Rich > > > > ------------------------------ > > _______________________________________________ > R-sig-ecology mailing list > [email protected] > https://stat.ethz.ch/mailman/listinfo/r-sig-ecology > > > End of R-sig-ecology Digest, Vol 78, Issue 16 > ********************************************* > [[alternative HTML version deleted]] _______________________________________________ R-sig-ecology mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-ecology
