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Definition

The log loss test measures the dissimilarity between predicted probabilities and the true distribution. Also known as cross-entropy loss or binary cross-entropy (in the binary classification case), it evaluates how well the model’s predicted probabilities match the actual class labels.

Taxonomy

  • Task types: Tabular classification, text classification.
  • Availability: and .

Why it matters

  • Log loss provides a probabilistic measure of classification performance, considering not just correctness but also confidence in predictions.
  • It heavily penalizes confident wrong predictions, making it sensitive to model calibration and overconfidence.
  • Lower log loss values indicate better model performance, with 0 representing perfect probability predictions.
  • This metric is particularly valuable when you need well-calibrated probability estimates, not just class predictions.

Required columns

To compute this metric, your dataset must contain the following columns:
  • Prediction probabilities: The predicted class probabilities from your classification model
  • Ground truths: The actual/true class labels
Log loss requires predicted probabilities, not just class labels. Ensure your model outputs probability estimates for each class.

Test configuration examples

If you are writing a tests.json, here are a few valid configurations for the log loss test: