Stable Isotope Sourcing Using Sampling

Erik B. Erhardt, Blair O. Wolf, Merav Ben-David, Edward J. Bedrick

Colorado School of Public Health, University of Colorado at Denver, Aurora, USA.
Department of Biology, University of New Mexico, Albuquerque, USA.
Department of Mathematics and Statistics, University of New Mexico, Albuquerque, USA.
Department of Zoology and Physiology, University of Wyoming, Laramie, USA.

DOI: 10.4236/oje.2014.46027                

Abstract

Stable isotope mixing models are used to estimate proportional contributions of sources to a mixture, such as in the analysis of animal diets, plant nutrient use, geochemistry, pollution, and forensics. We describe an algorithm implemented as SISUS software for providing a user-specified number of probabilistic exact solutions derived quickly from the extended mixing model. Our method outperforms IsoSource [1], a deterministic algorithm for providing approximate solutions to represent the solution polytope. Our method is an approximate Bayesian large sample procedure. SISUS software is freely available at StatAcumen.com/sisus and as an R package at cran.r-project.org/web/packages/sisus.

Keywords

SISUS, IsoSource, Mixing Model, Animal Ecology, Markov Chain Monte Carlo

Conflicts of Interest

The authors declare no conflicts of interest.

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