[2603.01339] Causal Effects with Unobserved Unit Types in Interacting Human-AI Systems

Statistics > Machine Learning arXiv:2603.01339 (stat) [Submitted on 2 Mar 2026] Title:Causal Effects with Unobserved Unit Types in Interacting Human-AI Systems Authors:William Overman, Sadegh Shirani, Mohsen Bayati View a PDF of the paper titled Causal Effects with Unobserved Unit Types in Interacting Human-AI Systems, by William Overman and 2 other authors View PDF HTML (experimental) Abstract:We study experiments on interacting populations of humans and AI agents, where both unit types and the interaction network remain unobserved. Although causal effects propagate throughout the system, the goal is to estimate effects on humans. Examples include online platforms where human users interact alongside AI-driven accounts. We assume a human-AI prior that gives each unit a probability of being human. While humans cannot be distinguished at the unit level, the prior allows us to compute the average human composition within large subpopulations. We then model outcome dynamics through a causal message passing (CMP) framework and analyze sample-mean outcomes across subpopulations. We show that by constructing subpopulations that vary in expected human composition and treatment exposure, one can consistently recover human-specific causal effects. Our results characterize when distributional knowledge of population composition (without observing unit types or the interaction network) is sufficient for identification. We validate the approach on a simulated human-AI platform driven ...