Causal GNNs: A GNN-Driven Instrumental Variable Approach for Causal Inference in Networks
This addresses the challenge of causal inference in network data for researchers and practitioners, offering a robust framework to handle hidden confounders, though it is an incremental improvement by integrating existing techniques like IVs and GNNs.
The paper tackles the problem of hidden confounders in causal inference within networks by proposing CgNN, a method that uses network structure as instrumental variables combined with GNNs and attention mechanisms, which effectively mitigates bias and improves estimation in real-world datasets.
As network data applications continue to expand, causal inference within networks has garnered increasing attention. However, hidden confounders complicate the estimation of causal effects. Most methods rely on the strong ignorability assumption, which presumes the absence of hidden confounders-an assumption that is both difficult to validate and often unrealistic in practice. To address this issue, we propose CgNN, a novel approach that leverages network structure as instrumental variables (IVs), combined with graph neural networks (GNNs) and attention mechanisms, to mitigate hidden confounder bias and improve causal effect estimation. By utilizing network structure as IVs, we reduce confounder bias while preserving the correlation with treatment. Our integration of attention mechanisms enhances robustness and improves the identification of important nodes. Validated on two real-world datasets, our results demonstrate that CgNN effectively mitigates hidden confounder bias and offers a robust GNN-driven IV framework for causal inference in complex network data.