🤖 AI Summary
Traditional causal inference methods struggle to handle structured data such as images and point clouds, primarily because the difference between potential outcomes may be undefined. This work proposes a Topological Causal Data Analysis (TCDA) framework that decouples the observed space, causal model, topological representation, and causal queries, distinguishing between outcome-level and distribution-level analyses. The framework establishes identifiability conditions and a doubly robust estimation procedure. By integrating Banach space–valued summaries, the g-formula, and topological representation theory, it constructs the first systematic mathematical foundation for causal inference with structured data. The study clarifies the auxiliary role of topology in causal analysis, introduces a target-oriented topological ignorability condition, and delineates the applicability boundaries of observed topologies in causal discovery.
📝 Abstract
Many modern outcomes, including images, point clouds, networks, and spatial fields, are structured objects for which \(Y^1-Y^0\) may be undefined or scientifically inadequate. We introduce \emph{Topological Causal Data Analysis} (TCDA), a framework separating the observation space, causal-model class, topological representation, and causal query. Topology does not define interventions; it supplies stable, shape-sensitive summaries after causal assumptions have been specified. We distinguish outcome-level TCDA, which transforms individual potential outcomes, from distribution-level TCDA, which transforms interventional outcome laws, and characterize when outcome and distribution level contrasts agree. Building on recent outcome-level theory, we formulate identification and doubly robust representations for Banach-space-valued summaries. At the distribution level, we identify targets through the standard causal \(g\)-formula and derive stability-transfer bounds and plug-in consistency. We also place target-specific topological ignorability within the framework, clarifying when a covariate-standardized coarse effect can be identified without identifying the full interventional laws. Finally, we delimit the role of observational topology in causal discovery: it can assist diagnosis on restricted model classes but cannot by itself identify causal structure.