Model Card: Bank + Telecom Churn Screening
Bank
Predictors: CreditScore, Age, Tenure, Balance, NumOfProducts, HasCrCard, IsActiveMember, EstimatedSalary, Geography.
Excluded identifiers: CustomerId, Surname.
Duplicate rows removed: 2. Train/validation/test: 6400/1600/2000.
Model: XGBoost; validation-selected F2 cutoff: 0.425; quality gate: demonstration.
Telecom
Predictors: SeniorCitizen, tenure, MonthlyCharges, TotalCharges, Partner, Dependents, PhoneService, InternetService, Contract, PaymentMethod.
Excluded identifiers: customerID.
Duplicate rows removed: 0. Train/validation/test: 3763/941/1176.
Model: XGBoost; validation-selected F2 cutoff: 0.100; quality gate: research_only_low_signal.
Methodology
Training-only preprocessing, validation PR AUC model selection, validation F2 threshold selection, untouched test performance.
Limitations
Educational datasets, distribution shift, no probability calibration, no subgroup fairness validation, and no downstream business impact study. For demonstration only.