A general approach to modeling and analysis of species abundance data with extra zeros



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.

Key Words

Covariate effects Extended Poisson process model Penalized likelihood Prediction 


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Copyright information

© International Biometric Society 2002

Authors and Affiliations

  1. 1.School of Land and Food SciencesThe University of QueenslandAustralia
  2. 2.School of Mathematics and StatisticsThe University of BirminghamU.K.
  3. 3.Walter and Eliza Hall Institute for Medical ResearchMelbourneAustralia

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