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 atests.json, here are a few valid configurations for the log loss test:
Related
- ROC AUC test - Area under the receiver operating characteristic curve.
- Accuracy test - Overall classification correctness.
- Precision test - Measure positive prediction accuracy.
- Recall test - Measure ability to find all positive instances.
- Aggregate metrics - Overview of all available metrics.

