Individual heterogeneity and identifiability in capture-recapture models

W.A. Link

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USGS · 5224429

Individual heterogeneity and identifiability in capture-recapture models

W.A. Link

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Abstract

Individual heterogeneity in detection probabilities is a far more serious problem for capture-recapture modeling than has previously been recognized. In this note, I illustrate that population size is not an identifiable parameter under the general closed population mark-recapture model Mh. The problem of identifiability is obvious if the population includes individuals with pi = 0, but persists even when it is assumed that individual detection probabilities are bounded away from zero. Identifiability may be attained within parametric families of distributions for pi , but not among parametric families of distributions. Consequently, in the presence of individual heterogeneity in detection probability, capture-recapture analysis is strongly model dependent.

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W.A. Link. 2004. Individual heterogeneity and identifiability in capture-recapture models. https://pubs.usgs.gov/publication/5224429

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