Measures for normalised abundance or abundances rated on a scale

Is your abundance data standardised by objects (rows)?

See our page on data transformations for more information on standardisation.

As an alternative...

As an alternative measure which relies on probabilistic logic, consider the Goodall's probabilistic coefficient (S23). This measure inversely weights the contribution of a given variable by that variable's probability of occurring across the objects in the data set. Thus, objects would be considered more similar if they shared similar values of less prominent variables. The value of the coefficient is the one complement of the probability that the similarity between two objects is due to chance alone. Several versions of this coefficient exist, adapted to different forms of data. See Legendre and Legendre (1998; Equation 7.31) for a discussion of a measure adapted for abundance data.