O F-Score, também conhecido como o Pontuação F1, is an métrica de avaliação for classificação binária models that balances precision and recall. It is particularly useful when the class distribution is imbalanced, meaning one class significantly outnumbers the other. The F-Score provides a single metric that combines both the precision (the ratio of true positive predictions to the total predicted positives) and recall (the ratio of true positive predictions to the actual positives).
A fórmula para calcular o F-Score é:
F1 Score = 2 * (Precisão * Recall) / (Precisão + Recall)
Onde:
- Precisão: The number of true positives divided by the number of true positives plus false positives.
- Recordar: The number of true positives divided by the number of true positives plus false negatives.
The F-Score ranges from 0 to 1, where a score of 1 indicates perfect precision and recall, while a score of 0 indicates the worst performance. An advantage of the F-Score is that it gives equal weight to precision and recall, making it more informative than accuracy sozinho, especialmente em casos onde uma classe é mais significativa que a outra.
Na prática, o F-Score é amplamente utilizado em várias áreas, incluindo processamento de linguagem natural, medical diagnosis, and any domain where the cost of false positives and false negatives is significant. By optimizing for the F-Score, practitioners can ensure a more balanced approach to model evaluation and improve overall model performance.