Beyond MAE: Phase 3 AutoGluon (IWPC-1780)
This repository contains the Phase 3 winning model from the pipeline described in "Beyond Mean Absolute Error: Ancestry-Stratified Calibration and Explainability for Warfarin Dosing Models", a nine-phase reproducible ML pipeline for warfarin dose prediction, trained on the IWPC-1780 cohort. An AutoGluon extreme_quality predictor on the combined clinical+genetic feature set reaches MAE 7.959, RΒ² 0.480, PW20 0.497, the best of 9 architectures Γ 3 feature sets evaluated on this cohort, with the stacking ensemble (RΒ² 0.479) essentially tied for second.
By: Hassan Barmandah, Omar Abdullah Bawazir, Siraj Aldeen Marghalani, Moath Shaat, Abdullah N. Alkattan, and Mariam M. AlEissa (corresponding author), Alfaisal University, Riyadh (with Umm Al-Qura University, Saudi Electronic University, Ministry of Health, Public Health Authority, King Khaled Eye Specialist Hospital Research Center, King Abdullah Petroleum Studies and Research Center)
This is a research artifact, not a validated clinical tool. It has not been evaluated prospectively and has no regulatory status.
Model Description
This model is an AutoGluon TabularPredictor fit with the extreme_quality preset on IWPC-1780 (n=1,780, n_test=356, fixed 80/20 patient-level split, seed 20260725), using the combined feature set (clinical + CYP2C9/VKORC1 genotype consensus). IWPC-1780 uses binary ancestry flags (Black, Asian) and pre-z-scored continuous features, and is evaluated independently rather than pooled with IWPC-6256. This is the best-performing model of 9 architectures evaluated across 3 feature sets on this cohort in the Phase 3 nested ablation.
Key Contributions
- Best Single Model on IWPC-1780: MAE 7.959 / RΒ² 0.480 / PW20 0.497, narrowly ahead of the stacking ensemble (RΒ² 0.479) and TabPFN (RΒ² 0.477), notably beating every individually-tuned model including CatBoost/TabPFN on this smaller cohort
- Combined-Feature Advantage: beats the same architecture family's clinical-only (RΒ² 0.296) and genetic-only (RΒ² 0.313) results on this cohort
- Independent Second-Cohort Replication: run with the identical AutoGluon configuration used on IWPC-6256, confirming the combined-feature advantage is not an artifact of one dataset
π How to Use
from autogluon.tabular import TabularPredictor
from huggingface_hub import snapshot_download
local_dir = snapshot_download("HassanB4/warfarisk-autogluon-1780")
predictor = TabularPredictor.load(local_dir)
prediction = predictor.predict(your_dataframe) # combined clinical+genetic features, see Training Data below
Input features: age, weight, height (pre-z-scored, not raw units; do not feed raw clinical values without re-harmonizing scale), binary ancestry flags (Black, Asian), CYP2C9 consensus, VKORC1.AA/VKORC1.AG genotype flags, amiodarone/enzyme-inducer comedication flags. See HasanBGit/WarfaRisk's src/warfarisk/phase3_genetics_ablation.py for the exact feature-engineering pipeline.
βοΈ Training Procedure
Training Data
| Split | Samples | Description |
|---|---|---|
| Training | 1,424 | 80% of IWPC-1780, patient-ID-level split |
| Test | 356 | Held out, seed 20260725 |
Hyperparameters
| Parameter | Value | Parameter | Value |
|---|---|---|---|
| Preset | extreme_quality |
Time Limit | 600s |
| Feature Set | combined (clinical + genetic) | Excluded Model Types | TABDPT, TABICL, TABM, MITRA |
| Split Seed | 20260725 | Split Level | Patient ID (not row) |
| Final Ensemble | WeightedEnsemble_L2 (blend of RealTabPFN-v2_r13/LightGBMPrep_r13/RealTabPFN-v2_r106) |
Leakage Audit | 11/11 checks passed |
Same excluded-model-type configuration as the IWPC-6256 run, applied for consistency across cohorts. Full run notes in docs/RESULTS.md and docs/KNOWN_ISSUES.md.
Models Compared (combined feature set, IWPC-1780)
| Model | MAE | RΒ² | PW20 |
|---|---|---|---|
AutoGluon extreme_quality |
7.959 | 0.480 | 0.497 |
| Stacking Ensemble | 7.993 | 0.479 | 0.514 |
| TabPFN | 8.018 | 0.477 | 0.483 |
| Linear Regression | 8.070 | 0.474 | 0.511 |
| CatBoost | 8.205 | 0.451 | 0.492 |
| Random Forest | 8.940 | 0.370 | 0.444 |
| MLP | 9.231 | 0.320 | 0.447 |
| Elastic Net | 9.404 | 0.286 | 0.449 |
| XGBoost | 10.583 | 0.165 | 0.396 |
π Evaluation Results
| Metric | Value |
|---|---|
| MAE (mg/week) | 7.959 |
| RΒ² | 0.480 |
| PW20 | 0.497 |
PW20 = proportion of predictions within 20% of the true dose (IWPC's own clinical-acceptability threshold is β₯0.50: this model comes within one point of clearing it, the closest of any model evaluated in this project).
Comparison Across Cohorts
| Cohort | MAE | RΒ² | PW20 |
|---|---|---|---|
IWPC-6256 (phase3-autogluon-iwpc6256) |
8.552 | 0.475 | 0.466 |
| IWPC-1780 (this model) | 7.959 | 0.480 | 0.497 |
β οΈ Limitations
- Research-Only: not validated prospectively, no regulatory status
- Pre-Scaled Features: this cohort's continuous features (age/weight/height) are pre-z-scored at source; do not pool raw inputs with IWPC-6256 without re-harmonizing scale
- Coarser Ancestry Encoding: IWPC-1780 only distinguishes Black/Asian/Other, unlike IWPC-6256's 14 labels; see
docs/RESULTS.mdfor this project's Phase 4/5 ancestry-fairness and calibration findings on this cohort - No Raw Data Shipped: the code repository does not redistribute IWPC data; see
data/DATA.md
π Acknowledgements
We thank the PharmGKB / International Warfarin Pharmacogenetics Consortium for the IWPC dataset, and the AutoGluon team for the AutoML framework this model was built with.
Related Links
π Citation
This model is described in the following manuscript, submitted to the MDPI journal AI and under review as of August 2026. The DOI below will be updated once the paper is formally published.
Barmandah, H.; Bawazir, O.A.; Marghalani, S.A.; Shaat, M.; Alkattan, A.N.; AlEissa, M.M. Beyond Mean Absolute Error: Ancestry-Stratified Calibration and Explainability for Warfarin Dosing Models. AI 2026, submitted.
@article{barmandah2026beyond,
title={Beyond Mean Absolute Error: Ancestry-Stratified Calibration and Explainability for Warfarin Dosing Models},
author={Barmandah, Hassan and Bawazir, Omar Abdullah and Marghalani, Siraj Aldeen and Shaat, Moath and Alkattan, Abdullah N. and AlEissa, Mariam M.},
journal={AI},
publisher={MDPI},
year={2026},
note={Manuscript submitted, under review as of August 2026. Cite the published DOI once assigned.}
}
π License
This project is licensed under the Apache 2.0 License. This model was fit on IWPC data; the fitted artifact and code are shared under Apache-2.0, but the underlying IWPC dataset is not redistributed by this repository; see HasanBGit/WarfaRisk's data/DATA.md for how to obtain it.
Collection including HassanB4/warfarisk-autogluon-1780
Evaluation results
- MAE on IWPC-1780 (International Warfarin Pharmacogenetics Consortium)self-reported7.959
- R2 on IWPC-1780 (International Warfarin Pharmacogenetics Consortium)self-reported0.480