Ablation Studies for Novel Treatment Effect Estimation Models

Hugo Gobato Souto; Francisco Louzada

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arXiv · 2410.15560

Ablation Studies for Novel Treatment Effect Estimation Models

Hugo Gobato Souto·Francisco Louzada

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Abstract

Ablation studies are essential for understanding the contribution of individual components within complex models, yet their application in nonparametric treatment effect estimation remains limited. This paper emphasizes the importance of ablation studies by examining the Bayesian Causal Forest (BCF) model, particularly the inclusion of the estimated propensity score $\hat{\pi}(x_i)$ intended to mitigate regularization-induced confounding (RIC). Through a partial ablation study utilizing a total of nine synthetic, we demonstrate that excluding $\hat{\pi}(x_i)$ does not diminish the model's performance in estimating average and conditional average treatment effects or in uncertainty quantification. Moreover, omitting $\hat{\pi}(x_i)$ reduces computational time by approximately 21%. These findings could suggest that the BCF model's inherent flexibility suffices in adjusting for confounding without explicitly incorporating the propensity score. The study advocates for the routine use of ablation studies in treatment effect estimation to ensure model components are essential and to prevent unnecessary complexity.

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Hugo Gobato Souto, Francisco Louzada. 2024-10-21. Ablation Studies for Novel Treatment Effect Estimation Models. https://arxiv.org/abs/2410.15560

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