AMS Special Seminar Series | Hui Zou

Location: Clark 110

When: March 4th at 10:00 a.m.

Title: High Dimensional Clustering via a Latent Transformation Mixture Model

Abstract: Cluster analysis is a fundamental task in machine learning. From the probabilistic modeling viewpoint, a finite mixture model is naturally suited for the distribution of data with multiple clusters, and hence model-based clustering (MBC) offers an effective solution. MBC has been successful in numerous applications. However, MBC also often underperforms when the model has significant modeling bias. We aim to design a more robust off-the-shelf MBC for high-dimensional data by reducing the model bias. To this end, we propose a novel CESME model by incorporating nonparametric latent transformations into the finite Gaussian mixture model (GMM). The inclusion of latent transformations significantly enhances the flexibility of the finite GMM without compromising interpretability. We derive a model fitting procedure for implementing the optimal clustering under CESME model and analyze the clustering accuracy of the resulting algorithm. It is shown that the additional cost due to estimating nonparametric transformations is negligible compared with an ideal clustering algorithm with known transformation. On six benchmark single cell RNA sequence datasets, CESME exhibits dominating advantages over existing methods in the literature.

Bio: Dr. Hui Zou is currently the inaugural Dr. Lynn Y.S. Lin Professor at the University of Minnesota. He earned his Ph.D. in Statistics from Stanford University in 2005. His primary research interests include statistical learning, high-dimensional models, statistical computing, and the application of modern statistical methods in business, health, and engineering. Dr. Zou is an elected fellow of the American Association for the Advancement of Science (AAAS), the Institute of Mathematical Statistics (IMS), and the American Statistical Association (ASA). He has published over 100 research articles, many of which are highly cited, including three that have been listed among the most-cited papers of all time in JRSSB, JASA, and JCGS. Dr. Zou has mentored 15 PhD students, two of whom received the COPSS Leadership Academy Award for Emerging Leaders in Statistics.

Zoom link: https://wse.zoom.us/j/92755277282?pwd=iULpLaFnWAcWl6tQYUbeyZaN3zwBzn.1