Skip to main content

**Seminars will be held In Person unless otherwise noted**

Seminar One

September 8, 2026
Griffin Floyd Hall, Room 100, 4pm to 5pm

Omiros Papaspiliopoulos
Università Bocconi

Title:

Variational inference for bilinear mixed models

Abstract:

The talk provides an overview of a book I am currently writing together with Max Goplerud (Department of Government at the University of Texas at Austin). The underlying modeling framework provides a unification of foundational model structures used throughout applied statistics, including GLMMs, GAMs, factor models/item response theory, spatial random effects, probabilistic matrix factorization, etc. I show three motivating applications: deep interactions for survey data, ideal point models for political ideology, and high-resolution demography. The situations we are interested in, involve large scale inference, where both the amount of training data and the number of model parameters are large, in the thousands or larger. We develop variational inference methods that are partly generic and partly tailored to these model structures, and some theory that establishes their properties in the large scale regime, in terms of convergence, uncertainty quantification and model selection. We have an associated modular, publicly availabe software in R, which is in synergy with lme4, mgcv, brms, and inla.

A couple of relevant recent publications:

Goplerud, M., Papaspiliopoulos, O. and Zanella, G. (2025) Partially factorized variational inference for high-dimensional mixed models,  Biometrika, 112:2 Pandolfi, A.,  Papaspiliopoulos, O. and Zanella, G. (2026) Conjugate gradient methods for high-dimensional GLMMs,  J. Amer. Statist. Assoc., 121(554), 1103–1115

Seminar Two

September 17, 2026
Griffin-Floyd Hall, Room 100, 4pm to 5pm

Kuan Liu
University of Toronto

Title:

Bayesian Causal Inference with Latent Variables for Cognitive Aging

Abstract:

Modifiable behavioural and psychosocial risk factors, including depression and loneliness, and environmental exposures such as heat and air pollution may contribute to accelerated cognitive aging and dementia risk. Motivated by the Canadian Longitudinal Study on Aging, this talk examines Bayesian causal inference when scientifically relevant variables are not directly observed. The first part presents a Bayesian nonparametric latent trajectory model for multivariate longitudinal cognitive outcomes, combined with posterior predictive standardization to estimate exposure effects on cognitive trajectory membership. The second part considers Bayesian sensitivity analysis for time-varying unmeasured confounding and its connection to ongoing work in environmental health, where individual-level exposure is latent. These examples showcase how Bayesian causal approaches can provide a flexible and principled framework for incorporating latent structure and uncertainty in challenging applied health research.

Seminar Three

October 1, 2026
Griffin-Floyd Hall, Room 100, 4pm to 5pm

Andrew Thomas
University of Iowa

Title:

TBD

Abstract:

TBD

October 15
Griffin-Floyd Hall, Room 100, 4pm to 5pm

Sumit Mukherjee
Columbia University

Title:

TBD

Abstract:

TBD

Seminar Five-Challis Lectures

October 29-30, 2026
Orange and Blue Room, O’Connell Center, 4pm to 5pm

Andrea Rotnitzky
University of Washington

Title:

TBD

Abstract:

Seminar Six

November 12, 2026
Griffin-Floyd Hall, Room 100, 4pm to 5pm

Hiya Bannerjee
Eli Lilly

Title:

TBD

Abstract:

TBD