Requirements & principles:
- Ensure regulatory compliance (BCBS, OCC, SOX), auditability, reproducibility, and timeliness for business iteration.
- Segregation of duties, risk-based controls, and lightweight developer-friendly workflows.
Governance & roles:
- Model Risk Committee (MRC): senior stakeholders (Head of Risk, Head of Data Science, Legal, Ops) — approves high-risk models, policy changes.
- Model Owner (Data Scientist/Product Lead): day-to-day model stewardship, documentation updates.
- Independent Validator (Model Validator/Quant Risk): independent testing, sign-off on validations/backtests.
- Change Approver (Risk Manager/Compliance): approves production changes.
- DevOps/ML Engineer: deployment, lineage, CI/CD.
- Audit Liaison: coordinates evidence for auditors.
Documentation (living artifacts):
- Model Card (required per model): purpose, version, inputs, data lineage, training & validation datasets, assumptions, intended population, performance metrics, business impact, limitations, approved usage, monitoring plan, retrain triggers, owners, last review date.
- Validation Report: methodology, benchmarks, stress/scenario tests, fairness and explainability results, threshold rationales.
- Change Log & Release Notes: dataset/schema changes, retrain, hyperparameter changes, feature drift notes.
Testing & backtesting cadence:
- Pre-deployment: unit tests, data schema checks, reproducibility test (seeded training), performance vs baseline, fairness checks, adversarial / sensitivity tests.
- Backtesting: monthly for high-impact models (credit scoring, approval), quarterly for medium, semi-annual for low. Backtest includes calibration (lift, ROC, KS), PSI for population shift, PD/LGD reconciliation, and economic scenario stress tests.
- Continuous monitoring: daily production data checks (data quality, feature distributions), weekly performance dashboards, alerting for threshold breaches (e.g., PSI>0.25, drop in AUC > X).
- Model retrain vs remediate decision tree in model card: auto retrain allowed for low-risk with guardrails; high-risk requires validator + MRC approval.
Approval flows:
- Dev builds + unit tests → Model Owner completes model card draft.
- Independent Validator runs validation/backtests → produces Validation Report.
- Risk Manager reviews findings; if acceptable, MRC approves for production; else returns for remediation.
- Post-deploy monitoring reports to MRC monthly; any breach triggers incident workflow and possible rollback.
Reporting & audit evidence:
- Standardized audit pack per model: model card, validation report, test scripts/results, code repository commit hashes, data snapshots, deployment records, monitoring logs, approval tickets.
- Dashboards (read-only for auditors): performance metrics, backtest history, drift indicators, recent changes.
- Retention policy: keep all artifacts, data snapshots, and code for 7+ years (or per regulation).
- Periodic review: annual full revalidation and ad-hoc upon material changes.
Balancing controls with iteration:
- Tiered control intensity by model risk classification (critical vs exploratory). Low-risk experimentation allowed in sandboxes with synthetic/anonymized data and clear labels; promotion to production requires full controls.
- Automate evidence collection (CI pipelines produce validation artifacts), automated monitoring, and templated model cards to minimize overhead.
- Pre-approved guardrails for retraining and threshold tuning to allow rapid, safe iterations.
This framework provides auditable artifacts and independent validation while enabling teams to iterate safely using automation, tiering, and clear approval gates.
