We have indicated some advantages of the Rsn method over correspondence analysis (CA) by numerical experiments on simulated data. In order to confirm these advantages over CA with actual fauna, we used published data on macrobenthos. For the comparison between CA and Rsn ordination, fuzzy cluster analysis was applied to each result of the ordination. Using the result of the fuzzy clustering of sites and species, we proposed some practical methods for the evaluation of the correspondence between site groups and species ones. With these methods, it was shown that the clustering of sites based on Rsn ordination corresponded better with that of species and gave more interpretable results than those based on CA. This means that Rsn ordination reflected more sensibly the species distribution patterns relatively free from noise. It was also shown that the fuzzy clustering of sites and species could provide useful tools to evaluate the correspondence between site groups and species ones. Therefore, the Rsn method together with fuzzy cluster analysis of sites and species is applicable to actual data such as benthic macrofauna.
