Metrics and Scoring Rules#

Metrics and scoring rules are quantitative measures used to evaluate the performance of a machine learning model. They help us to determine how well the model is able to make predictions, compared to the actual ground truth values.

Metrics Table#

A very comprehensive review can be found in torchmetrics: https://torchmetrics.readthedocs.io/en/latest/.

Problem Type

Metric

Description

Classification

Accuracy

The proportion of correct predictions made by a model, out of all the predictions.

Classification

Precision

The proportion of true positive predictions (i.e., the model correctly predicts that a sample belongs to a positive class) out of all positive predictions made by the model.

Classification

Recall

The proportion of true positive predictions made by the model out of all actual positive samples.

Classification

F1-Score

The harmonic mean of precision and recall, which provides a single value that balances both metrics.

Classification

AUC-ROC

The area under the Receiver Operating Characteristic curve, which measures the ability of a model to distinguish between positive and negative classes.

Regression

Mean Squared Error (MSE)

The mean of the squared differences between the predicted values and the true values.

Regression

Mean Absolute Error (MAE)

The mean of the absolute differences between the predicted values and the true values.

Regression

R-squared

The proportion of variance in the dependent variable that is explained by the independent variable.

Clustering

Silhouette Score

The mean similarity between a sample and all other samples in the same cluster, minus the mean similarity between a sample and all other samples in different clusters.

Clustering

Calinski-Harabasz Index

A ratio of between-cluster variance to within-cluster variance, used to evaluate the quality of a clustering solution.

Clustering

Davies-Bouldin Index

A measure of the average similarity between each cluster and its most similar cluster, used to evaluate the quality of a clustering solution.