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Statistical Development of Animal Density Estimation Using Random Encounter Modelling

Jourdain, Natoya O.A.S., Cole, Diana J., Ridout, Martin S., Rowcliffe, J. Marcus (2020) Statistical Development of Animal Density Estimation Using Random Encounter Modelling. Journal of Agricultural, Biological, and Environmental Statistics, 25 . pp. 148-167. ISSN 1085-7117. (doi:10.1007/s13253-020-00385-4) (KAR id:79919)


Camera trapping is widely used in ecological studies to estimate animal density, although these studies are largely restricted to animals that can be identified to the individual level. The random encounter model, developed by Rowcliffe et al. (J Anal Ecol 45(4):1228–1236, 2008), estimates animal density from camera-trap data without the need to identify animals. Although the REM can provide reliable density estimates, it lacks the potential to account for the multiple sources of variance in the modelling process. The density estimator in REM is a ratio, and since the variance of a ratio estimator is intractable, we examine and compare the finite sample performance of many approaches for obtaining confidence intervals via simulation studies. We also propose an integrated random encounter model as a parametric alternative, which is flexible and can incorporate covariates and random effects. A data example from Whipsnade Wild Animal Park, Bedfordshire, south England, is used to demonstrate the application of these methods.

Item Type: Article
DOI/Identification number: 10.1007/s13253-020-00385-4
Uncontrolled keywords: Abundance estimation; Random encounter model; Unmarked species
Subjects: Q Science > QA Mathematics (inc Computing science) > QA276 Mathematical statistics
Divisions: Divisions > Division of Computing, Engineering and Mathematical Sciences > School of Mathematics, Statistics and Actuarial Science
Depositing User: Diana Cole
Date Deposited: 03 Feb 2020 08:57 UTC
Last Modified: 09 Dec 2022 00:47 UTC
Resource URI: (The current URI for this page, for reference purposes)

University of Kent Author Information

Cole, Diana J..

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Ridout, Martin S..

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