A random split on a 2 percent brick-kiln defect table can put almost no defects in validation. Which split keeps the rare class in each slice?
Select an answer to reveal the explanation.
Short Explanation
Think of a 2 percent kiln defect class. A plain random split can put almost no defects in validation. Stratify on the label so each fold keeps the class rate.
Full Explanation
Use a stratified split when class imbalance would otherwise empty a fold. A plain random split can leave validation with almost no defects. Skipping the fold and Polly are not that split.