Re: [R-sig-eco] Measurement distance for proportion data

2014-05-13 Thread Zbigniew Ziembik
I am not sure, but it seems that your problem is related to compositional data analysis. You can probably use Aitchison distance to estimate separation between proportions. Take a (free) look at:

Re: [R-sig-eco] Measurement distance for proportion data

2014-05-13 Thread Rich Shepard
On Tue, 13 May 2014, Zbigniew Ziembik wrote: or (commercial): Aitchison, J. 2003. The Statistical Analysis of Compositional Data. The Blackburn Press. There's also: Analyzing Compositional Data with R by van den Boogaart, K. Gerald,Tolosana-Delgado, Raimon. Published by Springer in their

Re: [R-sig-eco] Measurement distance for proportion data

2014-05-13 Thread Jari Oksanen
Typical dissimilarity indices are of form difference/adjustment, where the adjustment takes care of forcing the index to the range 0..1, and handles varying total abundances / richnesses. If you have proportional data, you may not need the adjustment at all, but you can just use any index. That

Re: [R-sig-eco] Measurement distance for proportion data

2014-05-13 Thread Jari Oksanen
Typical dissimilarity indices are of form difference/adjustment, where the adjustment takes care of forcing the index to the range 0..1, and handles varying total abundances / richnesses. If you have proportional data, you may not need the adjustment at all, but you can just use any index. That

Re: [R-sig-eco] Measurement distance for proportion data

2014-05-13 Thread separent
I would also suggest to give a try to the Aitchison distance. To do so, you can use the “compositions” package. You transform the proportions to centered log-ratios or isometric log-ratios (clr and ilr functions, respectively), then compute the Euclidean distance through transformed data -