Time: Thursday, May 7, 2026, 4:00-5:00 p.m.

Venue: Guoshun Campus, Starr Building, Room 502

Moderator: Associate Professor Juan Shen, Department of Statistics and Data Science

Speaker: Emma Jingfei Zhang, Goizueta Foundation Chair Professor of Information Systems & Operations Management, Goizueta Business School, Emory University

Title: Designing Randomized Experiments under Network Interference

Abstract: Network interference occurs when a unit's outcome depends not only on its own treatment but also on the treatments received by connected units in the network. Experimental designs and analytical methods that ignore such interference can produce biased estimators of causal effects. In this talk, we develop a new experimental design for estimating the global treatment effect and spillover effect under a model-based framework and ego-cluster randomization. Under this design, the network is partitioned into a collection of ego-clusters, each consisting of a focal unit (the ego) and its network neighbors (the alters), with randomization conducted at the cluster level. We propose model-based estimators for the global treatment effect and spillover effect, and establish their consistency and asymptotic normality, with asymptotic variances determined by the ego-cluster structure. Building on these theoretical results, we further introduce an ego-clustering algorithm that sequentially selects egos and assigns alters to minimize asymptotic variances. Simulation studies and two empirical applications demonstrate that the proposed procedure yields accurate inference and efficiency improvements over existing network experimental designs.

Bio: Dr. Emma Jingfei Zhang is Goizueta Foundation Chair Professor of Information Systems & Operations Management at the Goizueta Business School of Emory University. Her research focuses on the analysis of large networks, tensors, and point processes, with applications in business, public health, and biomedical research. She is an elected member of the International Statistical Institute. She currently serves as Associate Editor of Journal of the American Statistical Association, The Annals of Applied Statistics, Statistica Sinica, and Journal of Computational and Graphical Statistics.