Event Date
Speaker: Sally Paganin (Research Fellow in the Department of Biostatistics at Harvard School of Public Health)
Title: Centered Partition Processes: Informative Priors for Clustering
Abstract: There is a very rich literature proposing Bayesian approaches for clustering starting with a prior probability distribution on partitions. Most approaches assume exchangeability, leading to simple representations in terms of Exchangeable Partition Probability Functions (EPPF). Gibbs-type priors encompass a broad class of such cases, including Dirichlet and Pitman-Yor processes. Even though there have been some proposals to relax the exchangeability assumption, allowing covariate-dependence and partial exchangeability, limited consideration has been given on how to include concrete prior knowledge on the partition. For example, we are motivated by an application in birth defect epidemiology, in which we wish to cluster birth defects into groups and we have prior knowledge of an initial clustering provided by experts. As a general approach for including such prior knowledge, we propose a Centered Partition process that modifies the EPPF to favor partitions close to an initial one. We use our method to analyze data from the National Birth Defect Prevention Study (NBDPS), relating different exposures to the risk of developing a birth defect, focusing on the class of Congenital Heart Defects. This is joint work with Amy Herring (Duke University), Andrew Olshan (UNC at Chapel Hill) and David Dunson (Duke University).
About the speaker: Sally Paganin is a Research Fellow in the Department of Biostatistics at Harvard School of Public Health, working on statistical methods for early cancer detection. Previously, she was a Postdoctoral researcher at UC Berkeley, where she worked on computational methods for Bayesian hierarchical models.
Seminar Date/Time: Thursday May 6th, 4:10pm
This seminar will be delivered remotely via Zoom. To access the Zoom meeting for this seminar, please contact the instructor Professor Jairo Fùquene Patiño or Pete Scully (pscully@ucdavis.edu) for the meeting ID and password, stating your affiliation.