F-measure

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Revision as of 13:06, 6 January 2023 by Bmackenty (talk | contribs)

The F-measure, also known as the F1 score, is a metric that is used to evaluate the performance of a binary classification model. It is defined as the harmonic mean of precision and recall, and is used to balance the precision and recall of a model in a single metric.

The F-measure is calculated using the following formula:

F-measure = 2 * (Precision * Recall) / (Precision + Recall)

Where precision is the proportion of true positive predictions made by the model, relative to the total number of positive predictions made by the model, and recall is the proportion of true positive predictions made by the model, relative to the total number of true positive cases in the data.

The F-measure is a useful metric when the goal of the classification model is to achieve a balance between precision and recall. It is often used in applications where it is important to minimize the number of false positives and false negatives, such as in spam filtering or medical diagnosis.

The F-measure can be interpreted as the harmonic mean of precision and recall, with a higher value indicating a better balance between precision and recall. It ranges from 0 to 1, with a higher value indicating a better performance of the model. However, it is important to note that the F-measure is sensitive to imbalanced class distributions, and may not be a reliable metric when the class distributions are highly imbalanced. In such cases, it may be more appropriate to use metrics such as the area under the precision-recall curve (AUPRC) or the area under the receiver operating characteristic curve (AUC).