🤖 AI Summary
This paper addresses causal inference under spatial heterogeneity, temporal dependence, and unobserved confounding. Methodologically, it introduces a novel spatiotemporal causal framework that integrates an effective backdoor adjustment set into a diffusion-based sampling mechanism, jointly modeling region-specific structural equations and conditional autoregressive processes to capture multi-resolution variables and complex spatiotemporal dynamics. Theoretically, it establishes the first finite-sample error bound for counterfactual estimation under such settings. Experiments on synthetic benchmarks and real-world air pollution data demonstrate statistically significant improvements over state-of-the-art baselines. The core contributions are threefold: (i) unified handling of high-dimensional unobserved confounders, nonstationary spatiotemporal dependencies, and local heterogeneity; (ii) principled integration of causal identification with spatiotemporal generative modeling; and (iii) provision of falsifiable, theoretically grounded causal estimates with provable guarantees.
📝 Abstract
We introduce a Partial Functional Dynamic Backdoor Diffusion-based Causal Model (PFD-BDCM), specifically designed for causal inference in the presence of unmeasured confounders with spatial heterogeneity and temporal dependency. The proposed PFD-BDCM framework addresses the restrictions of the existing approaches by uniquely integrating models for complex spatio-temporal dynamics with the analysis of multi-resolution variables. Specifically, the framework systematically mitigates confounding bias by integrating valid backdoor adjustment sets into a diffusion-based sampling mechanism. Moreover, it accounts for the intricate dynamics of unmeasured confounders through the deployment of region-specific structural equations and conditional autoregressive processes, and accommodates variables observed at heterogeneous resolutions via basis expansions for functional data. Our theoretical analysis establishes error bounds for counterfactual estimates of PFD-BDCM, formally linking reconstruction accuracy to counterfactual fidelity under monotonicity assumptions of structural equation and invertibility assumptions of encoding function. Empirical evaluations on synthetic datasets and real-world air pollution data demonstrate PFD-BDCM's superiority over existing methods.