Richard J. Barker

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Statistical thinking in wildlife biology and ecology has been profoundly influenced by the introduction of AIC (Akaike's information criterion) as a tool for model selection and as a basis for model averaging. In this paper, we advocate the Bayesian paradigm as a broader framework for multimodel inference, one in which model averaging and model selection(More)
We present a hierarchical extension of the Cormack-Jolly-Seber (CJS) model for open population capture-recapture data. In addition to recaptures of marked animals, we model first captures of animals and losses on capture. The parameter set includes capture probabilities, survival rates, and birth rates. The survival rates and birth rates are treated as a(More)
A postal survey was conducted regarding statistical techniques, research methods and software used in the workplace by 913 graduates with PhD and Masters degrees in the biological sciences, psychology, business, economics, and statistics. The study identified gaps between topics and techniques learned at university and those used in the workplace, and(More)
Quantifying long-term historical climate is fundamental to understanding recent climate change. Most instrumentally recorded climate data are only available for the past 200 years, so proxy observations from natural archives are often considered. We describe a model-based approach to reconstructing climate defined in terms of raw tree-ring measurement data(More)
In a mark-recapture study of an animal population, live-recapture information may be supplemented by resightings from marked animals obtained throughout the period of the study and the two types of data analyzed simultaneously. The resighting data can only contribute to estimates of survival probability if they are jointly modeled with the live-recapture(More)
Recently developed methods for analyzing mark–recapture data allow simultaneous modeling of information from a variety of animal encounters. Incor-poratingthis extra information in an analysis requires use of a more complicated model but can lead to improved precision of estimates. An important aspect of such joint models is that movement of animals to and(More)
Estimating abundance, age structure and sex ratio of a recently discovered New Zealand tusked weta Motuweta riparia (Orthoptera, Anostostomatidae), using mark-recapture analysis. Abstract: Estimates of abundance, age structure and sex ratio are essential for monitoring the status of populations. We report the first attempt to reliably estimate these(More)
Hierarchical modeling of abundance in space or time using closed-population mark-recapture under heterogeneity (model $$\hbox {M}_{\text {h}}$$ M h ) presents two challenges: (i) finding a flexible likelihood in which abundance appears as an explicit parameter and (ii) fitting the hierarchical model for abundance. The first challenge arises because(More)