Upper Midwest Environmental Sciences Center
Position title: Statistician
Ph.D. (Biostatistics), University of South Carolina, Columbia, SC, 2001
M.S. (Biology), University of Kentucky, Lexington, KY, 1993
Diploma in Natural Resources, Lincoln University, New Zealand, 1982
B.Sc. (Botany), University of Auckland, Auckland, New Zealand, 1981
For a full list of publications, click here.
Gray BR, V Lyubchich, YR Gel, JT Rogala, DM Robertson and X Wei. 2015. Estimation of river and stream temperature trends from irregular time series. Statistical Methods & Applications pp 1-17. Online First. DOI 10.1007/s10260-015-0334-7
McKann PC, BR Gray and WE Thogmartin. 2013. Small sample bias of dynamic occupancy models. Journal of Wildlife Management and Wildlife Monographs 77: 172-180.
Gray BR, MD Holland, F Yi, and LAH Starcevich. 2013. Influences of availability on parameter estimates from site occupancy models, with application to submersed aquatic vegetation. Natural Resource Modeling 26: 526-545.
Gray BR, JT Rogala and JN Houser. 2013. Treating floodplain lakes of large rivers as study units for variables that vary within lakes; an evaluation using chlorophyll a and inorganic suspended solids data from floodplain lakes of the Upper Mississippi River. River Research and Applications 29: 330-342.
Gray BR, AM Ray, JT Rogala, MD Holland and JD Houser. 2012. Spatial and temporal variation in duckweed and filamentous algal levels in contiguous floodplain lakes of the Upper Mississippi River. Journal of Aquatic Plant Management 50: 91-100.
Gray BR. 2012. Variance components estimation for continuous and discrete data, with emphasis on cross-classified sampling designs. In: Gitzen, R.A., J.J. Millspaugh, A.B. Cooper, D.S. Licht, editors. Design and analysis of long-term ecological monitoring studies. Cambridge University Press, pp. 200-227. Paper
Nielson RM, BR Gray, LL McDonald and PJ Heglund. 2011. Estimating site occupancy rates for aquatic plants using spatial sub-sampling designs when detection probabilities are less than one. Aquatic Botany 95: 221– 225
Toribio SG, BR Gray and S Liang. 2011. An evaluation of the Bayesian approach for fitting the N-mixture model for use with pseudo-replicated count data. Journal of Statistical Computation and Simulation. DOI:10.1080/00949655.2011.572881.
Holland MD and BR Gray. 2011. Multinomial mixture model with heterogeneous classification probabilities. Environmental and Ecological Statistics 18: 257–270.
Gray BR, W Shi, JN Houser, JT Rogala, Z Guan and JL Cochran. 2010. Cumulative effects of restoration efforts on ecological characteristics of an open water area within the Upper Mississippi River. River Research and Applications
Holland MD, G Meeden and BR Gray. 2010. A finite population Bayes procedure for censored categorical abundance data. Journal of the Indian Society of Agricultural Statistics 64: 171-175.
Gray BR, RJ Haro and JT Rogala. 2010. Addressing among-group variation in covariate effects using multilevel models. Environmental and Ecological Statistics 16: DOI 10.1007/s10651-009-0119-y
Smith DR, BR Gray, TJ Newton and D Nichols. 2009. Effect of imperfect detectability on adaptive and conventional sampling: simulated sampling of freshwater mussels in the Upper Mississippi River. Environmental Monitoring and Assessment 170: 499-507.
Gray BR, D Bushek, JW Drane and D Porter. 2009. Associations between land use and Perkinsus marinus infection of eastern oysters in a high salinity, partially urbanized estuary. Ecotoxicology 18: 259-269.
Li J, BR Gray and DM Bates. 2008. An empirical study of statistical properties of variance partition coefficients for multi-level logistic regression models. Communications in Statistics - Simulation and Computation 37: 2010 – 2026
Gray BR and MM Burlew. 2007. Estimating trend precision and power to detect trends across grouped count data. Ecology 88: 2364-2372.
Gray BR. 2005. Selecting a distributional assumption for modelling relative abundances of benthic macroinvertebrates. Ecological Modelling 185: 1-12
Gray BR, RJ Haro, JT Rogala and JS Sauer. 2005. Modeling fingernail clam (Family: Sphaeriidae) abundance-habitat associations at two spatial scales using hierarchical count models. J Freshwater Biology 50: 715-729
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