On Wed, Feb 8, 2012 at 4:10 PM, Caroline Wallis <[email protected]> wrote: > I am trying to use the 'adonis' function in the 'vegan' package to assess > differences in water depth and water velocity between areas of a river > channel categorised by surface flow type (6 types in total, unequal sample > sizes). > > Sample Data (LB): > > SFT Depth Vel > BSW 0.18 1.2 > BSW 0.16 1.03 > BSW 0.16 0.98 > BSW 0.22 0.53 > BSW 0.11 0.668 > BSW 0.14 0.432 > BSW 0.12 0.391 > BSW 0.16 0.647 > BSW 0.2 0.903 > BSW 0.3 0.594 > BSW 0.37 0.429 > .... > > The dependent data was used in data frame format, rather than a dissimilarity > matrix. > > Using the call > 'adonis(formula=SFT~Depth*Vel,data=LB,permutations=999,method="canberra",strata=NULL)' > I get the following error:
Dear Caroline, on a second thought I realized that you might want to flip the variables in your adonis() call so that "Depth" and "Vel" are the dependent variables and "SFT" the predictor. Something like: # create a dataframe containing the dependent variables; "sampledata" is the data frame you posted a sample of dep.var <- data.frame(sampledata[,2:3]) # extract the predictor variable pred.var <- sampledata[,1] # perform MANOVA model <- adonis(dep.var ~ pred.var, permutations = 999,method = "canberra", strata = NULL) Hope this helps, Ivailo -- UBUNTU: a person is a person through other persons. _______________________________________________ R-sig-ecology mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-ecology
