Guest talk: Jason Hartford

On February 5, 2026, Jason Hartford (University of Manchester) will give a guest talk on Learning the Shape and the Grammar of Cellular Responses, as part of ELLIS Institute Finland's faculty day. 

Date and time 

February 5, 2026, 14:15-15:00

Location

Lecture hall TU2, Maarintie 8, 02150 Espoo (Aalto University campus)

Abstract

Predicting the effects of experimental perturbations is a central goal in efforts to build virtual cell models. In this talk, I argue that progress along this direction depends on improving models along two distinct but interrelated axes. The first concerns accurately capturing the morphology of cellular responses, such as pixel-level phenotypes or transcriptomic structure. The second concerns learning the language or grammar by which perturbations combine across contexts. I illustrate these ideas using two recent works: one demonstrating how careful, systematic engineering of flow matching models can yield large gains in modeling cellular morphology, and another showing how even very simple models can achieve competitive performance by when given access to the right priors about how perturbations relate to each other. More generally, I will discuss how—despite massive datasets—language or grammar by which perturbations combine is better thought of a small-data problem, given combinatorial space of possible experiments. I will discuss three broad strategies for addressing this: efficiently increasing data coverage through experimental design, imposing inductive assumptions, and leveraging domain-specific prior knowledge.

Bio

Jason Hartford is the Dame Kathleen Ollerenshaw Fellow at the University of Manchester and Research Unit Lead / Staff Research Scientist at Valence Labs.