🤖 AI Summary
This study addresses the pervasive challenge of unobserved confounding in observational studies, particularly when confounders cannot be adequately captured by structured covariates. The authors propose a neural network–enhanced double machine learning (DML) framework that systematically leverages text embeddings as effective proxies for missing confounders embedded in high-dimensional unstructured data. The approach highlights the limitations of conventional tree-based models in handling the continuous topological structure of embedding manifolds and demonstrates that adapting deep learning architectures substantially improves debiasing performance. Empirical evaluation on synthetic benchmarks shows a dramatic reduction in causal estimation bias—from +24% to −0.86%—bringing estimates close to the true parameter value, thereby underscoring the critical role of deep learning in enabling robust text-based causal inference.
📝 Abstract
Estimating causal treatment effects in observational settings is frequently compromised by selection bias arising from unobserved confounders. While traditional econometric methods struggle when these confounders are orthogonal to structured covariates, high-dimensional unstructured text often contains rich proxies for these latent variables. This study proposes a Neural Network-Enhanced Double Machine Learning (DML) framework designed to leverage text embeddings for causal identification. Using a rigorous synthetic benchmark, we demonstrate that unstructured text embeddings capture critical confounding information that is absent from structured tabular data. However, we show that standard tree-based DML estimators retain substantial bias (+24%) due to their inability to model the continuous topology of embedding manifolds. In contrast, our deep learning approach reduces bias to -0.86% with optimized architectures, effectively recovering the ground-truth causal parameter. These findings suggest that deep learning architectures are essential for satisfying the unconfoundedness assumption when conditioning on high-dimensional natural language data