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Estimation of population size when capture probability depends on individual state

Worthington, H, McCrea, Rachel S., King, R, Griffiths, Richard A. (2018) Estimation of population size when capture probability depends on individual state. Journal of Agricultural, Biological, and Environmental Statistics, . ISSN 1085-7117. E-ISSN 1537-2693. (doi:10.1007/s13253-018-00347-x)


We develop a multi-state model to estimate the size of a closed population from

capture–recapture studies. We consider the case where capture–recapture data are not of

a simple binary form, but where the state of an individual is also recorded upon every

capture as a discrete variable. The proposed multi-state model can be regarded as a

generalisation of the commonly applied set of closed population models to a multi-state

form. The model allows for heterogeneity within the capture probabilities associated with

each state while also permitting individuals to move between the different discrete states.

A closed-form expression for the likelihood is presented in terms of a set of sufficient

statistics. The link between existing models for capture heterogeneity is established,

and simulation is used to show that the estimate of population size can be biased when

movement between states is not accounted for. The proposed unconditional approach is

also compared to a conditional approach to assess estimation bias. The model derived

in this paper is motivated by a real ecological data set on great crested newts, Triturus


Item Type: Article
DOI/Identification number: 10.1007/s13253-018-00347-x
Uncontrolled keywords: Abundance; Closed population; Individual heterogeneity; Transition probabilities.
Subjects: Q Science > QA Mathematics (inc Computing science) > QA276 Mathematical statistics
Divisions: Faculties > Sciences > School of Mathematics Statistics and Actuarial Science > Statistics
Depositing User: Rachel McCrea
Date Deposited: 09 Jun 2015 14:09 UTC
Last Modified: 01 Aug 2019 10:38 UTC
Resource URI: (The current URI for this page, for reference purposes)
McCrea, Rachel S.:
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