INFORMS CAP flashcards
INFORMS CAP · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Decision-relevant problem statement
- A framing that names the decision, decision maker, available actions, objective, and constraints, so that modeling effort maps to a real choice rather than a vague request.
- Counterfactual baseline
- The outcome the organization would achieve without the model, used as the reference against which any claimed model value is measured.
- Value of a model
- The improvement in decision outcomes attributable to the model minus the cost of building and operating it, expressed in the decision maker's units.
- Stakeholder role map
- An explicit list of sponsor, decision owner, data owner, and affected parties; a missing role predicts later deployment or adoption failure.
- Falsifiable success criteria
- A metric, baseline, target, evaluation window, and stop threshold agreed before work begins, allowing the project to be judged objectively.
- CRISP-DM phases
- Business understanding, data understanding, data preparation, modeling, evaluation, and deployment; the process is iterative rather than strictly linear.
- Causal versus predictive
- Predictive models estimate outcomes from observed features; causal questions require design-based identification such as randomization or instrumental variables.
- Cross-validation variants
- k-fold for independent data, stratified for imbalance, time-series split for temporal order, and group k-fold when entities repeat across folds.
- Regularization L1 versus L2
- L1 penalizes absolute coefficients and can zero them out for selection; L2 penalizes squares and shrinks coefficients smoothly without selection.
- Optimization formulation
- An explicit statement of decision variables, objective function, and constraints, checked for feasibility and boundedness before solver results are trusted.
- Missingness mechanisms
- MCAR means missing independently of values, MAR means predictable from observed data, and MNAR means depending on the unobserved value itself.
- Data leakage
- Use of information unavailable at decision time, or derived from the target, as a feature; it inflates validation scores and fails in production.
- Class imbalance reporting
- When positives are rare, report precision, recall, and PR-AUC rather than accuracy, and tune the decision threshold to the cost matrix.
- Data lineage record
- Documentation of source, extraction date, transformations, and owner for each field, enabling reproduction and audit of any model input.
- Sampling representativeness
- The evaluation sample must mirror the deployment population; otherwise measured performance will not transfer to live decisions.
- Bias-variance decomposition
- Expected prediction error equals squared bias plus variance plus irreducible noise; added model capacity typically lowers bias and raises variance.
- Overfitting signal
- Training error substantially below validation error; remedies include more data, regularization, a simpler model, or early stopping.
- Probability calibration
- Agreement between predicted probabilities and observed frequencies, checked with reliability curves and corrected by Platt scaling or isotonic regression.
- Threshold as business decision
- The operating point should be chosen from the relative cost of false positives and false negatives, not from an arbitrary default such as 0.5.
- Feature importance caveat
- Importance measures dependence within a fitted model and is not causal evidence; correlated features can distort permutation and split-based rankings.
- Reproducible model pipeline
- Fixed seeds, pinned library versions, versioned data snapshots, and a scripted path from raw data to final artifact that can be rerun exactly.
- Shadow deployment
- Running a model alongside current practice without acting on its output, to validate inputs, latency, and score distribution before decisions change.
- Training-serving skew
- Divergence between feature transformations in training and in production serving; a leading cause of silent model failure after release.
- Canary release with rollback
- A staged rollout to a small share of traffic with predefined error, latency, and drift triggers and an authorized owner who can revert.
- Deployment monitoring triad
- Tracking input distribution drift, output score distribution and calibration, and realized business outcomes, each with alert thresholds and owners.
- Joint artifact versioning
- Model artifact, code, configuration, and training data snapshot are versioned together so any historical prediction can be reproduced.
- Drift types
- Covariate drift changes input distribution, label drift changes target distribution, and concept drift changes the input-output relationship; responses differ.
- Retraining trigger
- A predefined condition for refitting a model: scheduled cadence, performance below threshold, drift beyond a control limit, or upstream data change.
- Independent model validation
- Review of a model by someone other than its developer, with documented findings and sign-off, required for high-risk production models.
- Model inventory
- A register recording purpose, owner, version, risk tier, data sources, validation results, and approval date for every production model.
- Fairness metric incompatibility
- Demographic parity, equalized odds, and predictive parity generally cannot all hold at once, so the chosen criterion must be justified by context.
- Honest reporting obligation
- Reporting negative findings, uncertainty, and all relevant runs, and never presenting correlational predictions as causal claims to decision makers.