Speaker: Sangwon Hyun, Postdoc, University of Southern California
Title: Sparse Multivariate Mixture of Experts for Learning Environmental Drivers of Marine Microbial Systems
Abstract:
Although microscopic, phytoplankton in the ocean are extremely important to all of life and are together responsible for as much photosynthesis as all plants on land combined. Today, oceanographers are able to collect flow cytometry data in real time while onboard a moving ship, providing them with fine-scale information about the distribution of phytoplankton across thousands of kilometers. We present a novel sparse multivariate mixture of experts model to estimate the time-varying phytoplankton subpopulations while simultaneously identifying the specific environmental covariates that are predictive of the observed changes to these subpopulations. We apply this model to data from numerous oceanographic ships deployed to the North Pacific ocean, and learn new insights about the relationship between microbial populations in the ocean and environmental factors.
