Dear all, apologies for the simplicity of my question, maybe it has been asked many times, but I am a total novice to CCA. I have performed a CCA using a series of environmental variables that comprise a mixture of categorical and non-categorical variables. What I do not understand is why when I change the order of my variables and I plot the results, a variable disappears from the CCA biplot i.e. the last one being continuous variable. I realised that there might a very simple question, so I would be happy even with a reference where to find an answer. Below some code showing what is happening.
thanks in advance, Simone require(RCurl) require(vegan) x <- getURL("https://dl.dropboxusercontent.com/u/33966347/testdata.csv") dat<- read.csv(text = x) # example 1 x7 disappear from the plot (note that x5 and x6 are categorical) ccatest<-cca(dat[8:144]~x1+x2+x3+x4+x5+x6+x7,data=dat) plot(ccatest) # example 2 x7 is present in the plot ccatest1<-cca(dat[8:144]~x7+x1+x2+x3+x4+x5+x6,data=dat) plot(ccatest1) _______________________________________________ R-sig-ecology mailing list R-sig-ecology@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-ecology