juniorModel Evaluation
What is cross-validation?
Updated May 17, 2026
Short answer
Cross-validation evaluates a model using multiple train-test splits.
Deep explanation
It splits data into k folds, training on k-1 folds and testing on the remaining fold iteratively.
Real-world example
Used in medical diagnosis models to ensure robustness across datasets.
Common mistakes
- Using CV on time-series without proper splitting.
Follow-up questions
- What is k-fold CV?
- When not to use CV?