🤖 AI Summary
This study addresses the challenge of identifying causal treatment effects in the presence of unobserved spatially varying confounders. The authors develop a linear causal model that parameterizes the spatial covariance structure between the exposure and the unobserved confounder, establishing a general identifiability framework applicable to both discrete and continuous spatial data. Under mild conditions on the spatial configuration of observed locations and the association between exposure and confounding, the work provides the first systematic proof of identifiability for treatment effects across several commonly used spatial models. It also delineates precise boundary cases where identifiability fails, thereby offering a rigorous theoretical foundation for robust causal inference in spatial settings.
📝 Abstract
The study of causal effects in the presence of unmeasured spatially varying confounders has garnered increasing attention. However, a general framework for identifiability, which is critical for reliable causal inference from observational data, has yet to be advanced. In this paper, we study a linear model with various parametric model assumptions on the covariance structure between the unmeasured confounder and the exposure of interest. We establish identifiability of the treatment effect for many commonly 20 used spatial models for both discrete and continuous data, under mild conditions on the structure of observation locations and the exposure-confounder association. We also emphasize models or scenarios where identifiability may not hold, under which statistical inference should be conducted with caution.