Discussing the article: "An introduction to Receiver Operating Characteristic curves"

 

Check out the new article: An introduction to Receiver Operating Characteristic curves.

ROC curves are graphical representations used to evaluate the performance of classifiers. Despite ROC graphs being relatively straightforward, there exist common misconceptions and pitfalls when using them in practice. This article aims to provide an introduction to ROC graphs as a tool for practitioners seeking to understand classifier performance evaluation.

Many real-world applications involve binary classification problems, where instances belong to one of two mutually exclusive and collectively exhaustive classes. A prevalent instance of this scenario arises when a single target class is defined, and each instance is categorized as either a member of this class or its complement.  Consider, for example, radar signal classification, where a detected outline on a screen is categorized as either a tank (the target class) or a non-tank object.  Similarly, a credit card transaction can be classified as either fraudulent (the target class) or legitimate.

Target Or Not?

This specific formulation of the binary classification problem, characterized by the identification of a single target class, forms the basis for subsequent analysis.  Rather than explicitly assigning instances to one of two distinct classes, the approach adopted here focuses on determining whether an instance belongs to the designated target class.  While the terminology employed, referencing "target" and its complement, may evoke military connotations, the concept is broadly applicable.  The target class can represent various entities, such as a malignant tumor, a successful financial trade, or, as previously mentioned, a fraudulent credit card transaction.  The essential characteristic is the duality of the class of primary interest and all other possibilities.


Author: Francis Dube