Description:

Bo Li
UIUC

Title: Detection of local differences between two spatiotemporal random fields

Abstract: Comparing the characteristics of spatiotemporal random fields is often at demand. However, the comparison can be challenging due to the high-dimensional feature and dependency in the data. We develop a new multiple testing approach to detect the local difference in the characteristics of two spatiotemporal random fields by taking the spatial information into account. Our method adopts a two-component mixture model for location wise p-values and then derives a new false discovery rate (FDR) control, called mirror procedure, to determine the optimal rejection region. This procedure is robust to model misspecification and allows for weak dependency among hypotheses. To integrate the spatial heterogeneity, we model the mixture probability as well as allow the alternative distribution to be spatially varying. An EM-algorithm is developed to estimate the mixture model and implement the FDR procedure. We study the FDR control and the power of our new approach both theoretically and numerically, and finally apply the approach to compare the mean and teleconnection pattern between two synthetic climate fields.

Biography: Dr. Bo Li is a Professor and Chair in Department of Statistics at University of Illinois at Urbana-Champaign. She received her PhD in Statistics from Texas A&M University in 2006, and then became a Post-Doc at National Center for Atmospheric Research before joining Purdue as an Assistant Professor in 2008. In 2013 she moved to University of Illinois at Urbana-Champaign. Dr. Li’s research mainly focuses on spatial and spatio-temporal statistics and environmental statistics concerning problems in climatology, atmospheric sciences, public health, forestry and agriculture. Dr.  Li has served on the editorial boards of several journals including the Journal of the American Statistical Association and Environmetrics, and was guest editor for a special issue in Statistica Sinica and special issue in Journal of Agricultural, Biological and Environmental Statistics. Her research has been funded by the  NSF, NIH, NASA and Sandia National Laboratories. Dr. Li was the recipient of the Young Investigator Award in the ASA section on statistics and the environment and is a Fellow of the American Statistical Association.