Competition portfolio

This index separates the general Arena documentation from the technical history of each Kaggle challenge.

Competition	Status	Best verified result	Pages
Playground Series S6E2 — Predicting Heart Disease	Completed case study	Private ROC-AUC 0.95535; displayed winner score matched by late submission	Playground-Series-S6E2 · Evidence audit
PTCG AI Battle Challenge Playground	Active	Local CABT baseline validated; no Kaggle submission yet	PTCG-AI-Battle-Playground

Required page structure

Each future competition page includes the problem and metric, dataset/leakage audit, frozen validation contract, experiment ledger, compute environment, final design, separated OOF/Public/Private evidence, reproducibility boundary, skills and prompting decisions, limitations, and reusable lessons.

New competitions add a row here, a report under docs/competitions/, and implementation under src/competitions/.