arXiv Machine Learning

Splitting the Difference: Interpretable Causal Forests for Treatment Effect Heterogeneity and Bias

The paper introduces a new algorithm that uses decision trees and random forests to estimate individual treatment effects while providing interpretability. It modifies the standard random forest splitting criterion by combining a heterogeneity-focused criterion with a bias-correction criterion, enabling the model to handle observational studies with varying treatment propensities without separately estimating propensity scores. The resulting tree structure directly reveals which features drive treatment effect differences, and simulation studies show the method matches or surpasses existing approaches in prediction accuracy while improving interpretability.

arXiv Machine Learning
Sep 25

Feature Space Selection and Heterogeneous Effect Estimation for Blood-Brain Barrier Permeability: A Random Forest to the Generalized Random Forest Pipeline

The study evaluates how different molecular feature spaces—Morgan fingerprints, RDKit physicochemical descriptors, and SMILES bigrams—affect the prediction of blood‑brain barrier permeability using various learning algorithms. Dynamic Random Forests with combined features achieved the best performance (mean AUC 0.970). When applying Generalized Random Forests to estimate heterogeneous effects of LogP on BBB permeability, orthogonalization revealed that apparent heterogeneity largely vanished after accounting for confounding, shifting importance toward residual SMILES bigram information.

By Tshemollo Rapolai, Seite Makgai, Mohammad Arashi
arXiv Machine Learning
Aug 11

Demystifying Prediction Powered Inference

arXiv:2601. 20819v2 Announce Type: replace-cross Abstract: Machine learning predictions are increasingly used to supplement incomplete or costly-to-measure outcomes in fields such as biomedical research, environmental science, and social science.

By Yilin Song, Dan M. Kluger, Harsh Parikh, Tian Gu
arXiv Machine Learning
Jul 30

From Unsupervised Subgroups to Hypothetical State-Intervention Policies: An Evaluation of Selected Subgrouping Methods in Observational Health Data

arXiv:2607. 26521v1 Announce Type: new Abstract: Conventional subgroup analyses can yield unstable and difficult-to-interpret conclusions, especially in observational biomedical data where each individual is observed under only one exposure state, true individual treatment effects are unavailable, and causal structure is uncertain.

By Vasundhara Acharya, Bulent Yener
arXiv AI
Oct 9

Prediction-Powered Data Fusion for Treatment Effect Estimation

The paper introduces a framework that fuses data from a small randomized controlled trial (RCT) with a large observational study (OBS) to estimate treatment effects without imposing special assumptions on the OBS. It presents an ATE estimator called AIPW‑Fusion, which uses closed‑form weights and confidence intervals, and two conditional ATE (CATE) learners, DR‑Fusion and R‑Fusion, that preserve unbiasedness while borrowing precision from the OBS. Experiments validate the proposed methods.

By Yonghan Jung, Shu Yang