I am working on the development of multi-species volume allometric equation from diameter (DBH). I would like to form groups of species with the largest possible volume-diameter correlations by making a supervised classification (according to the functional traits of the species, phytogeographic area etc.) and an unsupervised classification (using classification algorithms). And between HAC, Kmeans and Random Forest what should i choose (Obviously I will try all algorithm and choose the best fit).Thank you for your suggestions and your help.