Rao's quadratic entropy as a measure of functional diversity based on multiple traits

Question: Is Rao's quadratic entropy a suitable measure of functional diversity if several traits are considered? Methods: It is checked whether Rao's quadratic entropy (FDQ) satisfies a priori criteria suggested by Mason et al. A real data set is used to show that there are often zeros in abundance distributions which maximize functional diversity. Results and Conclusion: FDQ fulfils all a priori criteria and it surpasses other proposed...