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mdscheuerell
Real Name
Mark Scheuerell

Bio
Mark studies how natural processes and anthropogenic factors interact to drive ecological dynamics. Much of his research focuses on the effects of climate variability and human activities on Pacific salmon populations and the aquatic ecosystems they inhabit. Mark has been with the NWFSC since 2003 and is also an affiliate assistant professor in the School of Aquatic and Fisheries Sciences at the University of Washington. Mark holds a B.S. in Zoology from the University of Wisconsin, an M.S. in Fisheries and Aquatic Sciences from Cornell University, and a Ph.D. in Zoology from the University of Washington.

Mark uses a combination of simulation and statistical modeling approaches to investigate the spatial and temporal dynamics of aquatic ecosystems.


Projects


  • Bayesian MAR(1) model

    This set of Matlab scripts conducts a first order MAR(1) model to estimate interactive effects, and covariate effects, on a time series of data from a community.

    It uses a Gibbs sampler to estimate parameters, and currently is set up with diffuse priors on all parameters for the model. It is pretty basic at this point, but it works.

    Note on the Gamma distribution:

    Going back and forth between Matlab/R/WinBUGS can be confusing, because of the different parameterizations of the gamma pdf. Here's the Matlab/BUGS forms and the R equivalents:

    Matlab: X ~ g(a,b) E[X] = ab

    R equivalent: X ~ g(shape=a,scale=b)

    BUGS: X ~ g(a,b) E[X] = a/b

    R equivalent: X ~ g(shape=a,rate=b) OR

    X ~ g(shape=a,scale=1/b)

  • Estimating heritability from time series

    by mdscheuerell, last updated 1/5/11, sharing set to Public
    kalman filter
    model averaging
    R
    State-space
    Time series analysis

    We use a multivariate state-space model and a time series of yearly migration dates for sockeye salmon to estimate the heritability coef from the classic breeder's equation.

    The 2 files below are the dataset and the R script.


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