juniorLogistic Regression
What is Log Loss?
Updated May 17, 2026
Short answer
Log loss measures the performance of classification models based on predicted probabilities.
Deep explanation
Lower log loss indicates better probability calibration. It penalizes incorrect confident predictions heavily.
Real-world example
Used in Kaggle competitions for evaluating classifiers.
Common mistakes
- Using accuracy alone without probability evaluation.
Follow-up questions
- Why is log loss differentiable?
- Can log loss be negative?