Abstract: The study of diversity in ecology is in crisis. The use of inappropriate methods is resulting in misleading analyses and interpretations. The multinomial diversity model, MDM, is a new method for relating Shannon diversity to complex environmental, spatial and temporal predictors. It is based on a parameterised formulation of Shannon entropy and diversity, and a novel link between entropy and the log-likelihood of the multinomial model. Model effects can be expressed as changes in entropy. Entropy can be partitioned within and between sites, species and models, and changes in entropy can be attributed to model predictors. This greatly enhances our capacity to model complex data sets, and yet also provide simple interpretations. By formulating diversity as a statistical model, analyses are extended beyond traditional simple hierarchies of α, β, γ and measures of turnover. Two example analyses illustrate the theoretical concepts and the analytical methods. The MDM R-package that implements the model is available on CRAN.
Biography: Glenn De’ath is a statistician and ecological modeller who works as Principal Research Scientist at the Australian Institute of Marine Science (AIMS) in Townsville. He has studied in mathematics, hydrodynamics, social-psychology and environmental methods. His research involves (1) the development of statistical methods for ecologists and has included multivariate regression trees, extended dissimilarity, principal curves, boosted trees and the multinomial diversity model, and (2) analysis of complex ecological-environmental systems.