Spatial aggregation of the Colorado potato beetle described by an exponential dispersion model

A statistical model to describe the spatial distribution of organisms within their environment is described based on the theory of exponential dispersion models. The model was based on a compound Poisson-negative binomial (PNB) distribution, derived from a scale invariant exponential dispersion model. Consequent to this scale invariance, the model manifested a power function relationship between the variance and the mean. When the model was applied to data from the distribution of the beetle, Leptinotarsa decemlineata, it was found to agree very well with observation.