title: The neglected tool in the Bayesian ecologist's shed: a case study testing informative priors' effect on model accuracy.
abstract: Despite benefits for precision, ecologists rarely use informative priors. One reason that ecologists may prefer vague priors is the perception that informative priors reduce accuracy. To date, no ecological study has empirically evaluated data-derived informative priors' effects on precision and accuracy. To determine the impacts of priors, we evaluated mortality models for tree species using data from a forest dynamics plot in Thailand. Half the models used vague priors, and the remaining half had informative priors. We found precision was greater when using informative priors, but effects on accuracy were more variable. In some cases, prior information improved accuracy, while in others, it was reduced. On average, models with informative priors were no more or less accurate than models without. Our analyses provide a detailed case study on the simultaneous effect of prior information on precision and accuracy and demonstrate that when priors are specified appropriately, they lead to greater precision without systematically reducing model accuracy.
authors: Quantitative and Applied Ecology Group, The School of Botany, The University of Melbourne Melbourne, Victoria, Australia.
authors: William K
authors: WK
authors: Morris
authors: Quantitative and Applied Ecology Group, The School of Botany, The University of Melbourne Melbourne, Victoria, Australia.
authors: Peter A
authors: PA
authors: Vesk
authors: Quantitative and Applied Ecology Group, The School of Botany, The University of Melbourne Melbourne, Victoria, Australia.
authors: Michael A
authors: MA
authors: McCarthy
authors: Thai National Parks Wildlife and Plant Conservation Department Bangkok, Thailand.
authors: Sarayudh
authors: S
authors: Bunyavejchewin
authors: Department of Forest and Ecosystem Science, Melbourne School of Land and Environment, The University of Melbourne Melbourne, Victoria, Australia.
authors: Patrick J
authors: PJ
authors: Baker
keywords: Ecological data; model precision; model validation; tree mortality
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