STOAT: Spatial-Temporal Probabilistic Causal Inference Network
Yang Yang, Du Yin, Hao Xue, Flora Salim
TL;DR
STOAT addresses the challenge of forecasting spatial-temporal causal time series with calibrated uncertainty by integrating a spatially informed causal adjustment mechanism into a deep probabilistic forecasting framework. It extends Difference-in-Differences through a learnable spatial relation matrix to obtain causally adjusted representations that capture both treatment effects and spatial spillovers, then feeds these into a neural encoder-decoder to produce distributional forecasts across regions. Empirical evaluation on multi-country COVID-19 data shows STOAT variants achieving superior CRPS and Energy Score compared with leading probabilistic forecasters, with clear gains during periods of strong interventions and spatial dependence. Ablation studies confirm the complementary value of spatial causal inference and covariate integration for robust probabilistic forecasting in STC-TS. The framework offers a principled approach to epidemic management and other spatial-temporal tasks where interventions and spatial connectivity drive uncertainty, while pointing to future work on dynamic spatial dependencies and mixture models for greater flexibility.
Abstract
Spatial-temporal causal time series (STC-TS) involve region-specific temporal observations driven by causally relevant covariates and interconnected across geographic or network-based spaces. Existing methods often model spatial and temporal dynamics independently and overlook causality-driven probabilistic forecasting, limiting their predictive power. To address this, we propose STOAT (Spatial-Temporal Probabilistic Causal Inference Network), a novel framework for probabilistic forecasting in STC-TS. The proposed method extends a causal inference approach by incorporating a spatial relation matrix that encodes interregional dependencies (e.g. proximity or connectivity), enabling spatially informed causal effect estimation. The resulting latent series are processed by deep probabilistic models to estimate the parameters of the distributions, enabling calibrated uncertainty modeling. We further explore multiple output distributions (e.g., Gaussian, Student's-$t$, Laplace) to capture region-specific variability. Experiments on COVID-19 data across six countries demonstrate that STOAT outperforms state-of-the-art probabilistic forecasting models (DeepAR, DeepVAR, Deep State Space Model, etc.) in key metrics, particularly in regions with strong spatial dependencies. By bridging causal inference and geospatial probabilistic forecasting, STOAT offers a generalizable framework for complex spatial-temporal tasks, such as epidemic management.
