v2.0 — Phase C v2 production deploy + Phase E external validation
v2.0 Release
Educational prototype for AI-assisted multiclass skin lesion classification on the HAM10000 dataset. Non-commercial use only (CC BY-NC 4.0 datasets). Not a medical device.
Headline Results
| Metric | HAM10000 test (in-distribution) | ISIC 2019 (external, HAM-disjoint) |
|---|---|---|
| v2 ResNet50 melanoma recall | 73.40% | 37.09% |
| v2 ResNet50 macro F1 | 70.08% | 34.72% |
| v2 ResNet50 test ECE (calibrated) | 0.0248 | 0.1814 |
| v1 4-model ensemble macro F1 | 74.10% | 41.24% |
Key honest finding: the in-distribution +18.6 pp melanoma recall improvement from Phase C does not generalize to external (ISIC 2019) data — mel recall drops to ~37%. A three-line preprocessing audit confirmed this is genuine distribution shift, not a pipeline artefact. The strong in-distribution number does not generalize; this is an educational prototype, not a medical device.
What's In This Release
- 6 model checkpoints: 4 v1 baseline models (ResNet50, DenseNet121, EfficientNet-B0, MobileNetV3-small), v2 ResNet50 winner (focal loss + balanced sampler), and v1 ResNet50 backup for rollback.
- FastAPI backend with calibrated single-model
/predict, 4-model ensemble/predict-ensemble, and Grad-CAM/predict-cam. - Flutter mobile UI prototype (clinical-style 5-screen layout).
- Reproducibility:
requirements-lock.txt,scripts/run_demo.sh/run_demo.ps1,scripts/download_checkpoints.pywith SHA256 verification.
Installation
CPU-only inference, ~250 MB checkpoint download, API ready at http://127.0.0.1:8126.
bash scripts/run_demo.sh # macOS / Linux
powershell -ExecutionPolicy Bypass -File scripts\run_demo.ps1 # WindowsSee README Quick Start for full prerequisites and troubleshooting.
Phase Highlights
- Phase C — focal loss + balanced sampler lifts melanoma recall from 54.79% to 73.40% on HAM10000 (single-model ResNet50).
- Phase E — honest external validation on a HAM10000-disjoint subset of ISIC 2019 (4,353 images). Documents distribution shift, calibration OOD failure, and bias audit limitations.
- Phase F — dependency lock, CPU-only deployment scripts, release packaging, Docker design (build deferred to future work).
Full Documentation
docs/release_v2.0.md— comprehensive release notesdocs/phase_e_external_validation.md— external validation findings + preprocessing auditdocs/licenses.md— full dataset citations and license terms
Citation
MIT for code; CC BY-NC 4.0 propagates to weights via HAM10000. See LICENSE.
HAM10000 citation:
Tschandl P., Rosendahl C. & Kittler H. The HAM10000 dataset, a large collection of multi-source dermatoscopic images of common pigmented skin lesions. Scientific Data 5, 180161 (2018). doi:10.1038/sdata.2018.161