Binary Classification Metrics: An Overview of ROC Curve and AUC

btd
2 min readNov 15, 2023
Photo by Sufyan on Unsplash

The Receiver Operating Characteristic (ROC) curve and the Area Under the ROC Curve (AUC) are widely used in binary classification tasks to evaluate the performance of a classification model. These metrics provide insights into the trade-off between the true positive rate and the false positive rate at different classification thresholds.

I. Receiver Operating Characteristic (ROC) Curve:

The ROC curve is a graphical representation of a classification model’s performance across various threshold settings. It plots the True Positive Rate (TPR), also known as sensitivity or recall, against the False Positive Rate (FPR), which is equal to 1−Specificity.

1. True Positive Rate (Sensitivity/Recall):

  • TPR=True Positives / (True Positives + False Negatives)

2. False Positive Rate:

  • FPR=False Positives / (False Positives​ + True Negatives)

A point on the ROC curve represents the performance of the classifier at a specific threshold. The curve helps visualize the trade-off between sensitivity and specificity.

3. Interpreting the ROC Curve:

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