K-Fold Cross-Validation Calculator
Split data into k folds for cross-validated evaluation
About K-Fold Cross-Validation
K-fold CV divides data into k equal parts, using each part once as a test set while training on the remaining k-1 parts.
Common choices for K:
- K=5: Good balance of bias and variance
- K=10: Most common choice, slightly lower bias
- K=n (LOOCV): Lowest bias but highest variance
Formula: CV(k) = (1/k) * Sum of test errors across folds