On Mon, 10 Oct 2011, Dave Roberts wrote:
I want to compare the results of the two sampling exercises in order to test the performance of the two sampling techniques.
I would try something pretty direct. Any appeal to differences in dissimilarities confounds the effects with the particular dissimilarity/distance matrix you use. Assuming the samples and species are in the same order, and that the data.frames are the same size, you might try
I did not read the original message, so I hope you'll allow me to join the thread. My recommendation is to use univariate tree models, particularly a classification tree (for ordinal explanatory variables; i.e., ST1 and ST2). This is fully, carefully, and non-technically explained in Chapter 9 (particularly Sections 9.3 and 9.4) in Zuur, Ieno, and Smith "Analysing Ecological Data." For that matter, I highly recommend reading the whole book. Rich _______________________________________________ R-sig-ecology mailing list R-sig-ecology@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-ecology
