Abstract
A general method for the analysis of ecological count data with extra zeros is presented using a Markov birth process representation of discrete distributions. The method uses a non parametric formulation of the birth process to model the residual variation and therefore allows the data to play a greater role in determining an appropriate distribution. This enables a more critical assessment of covariate effects and more accurate predictions to be made. The approach is also presented as a useful diagnostic tool for suggesting appropriate parametric models or verifying standard models. As an ill ustrative example, data describing a bundance of a species of possum from the montane ash forests of the central highlands of Victoria, southeast Australia, is considered.
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Podlich, H.M., Faddy, M.J. & Smyth, G.K. A general approach to modeling and analysis of species abundance data with extra zeros. JABES 7, 324–334 (2002). https://doi.org/10.1198/108571102221
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DOI: https://doi.org/10.1198/108571102221