Metrics for Multi-Class Classification: an Overview
It provides a practical overview for researchers and practitioners working on multi-class classification tasks, but it is incremental as it synthesizes existing metrics without introducing new ones.
The paper reviews and compares various performance metrics for multi-class classification, highlighting their advantages, disadvantages, and applications in model evaluation and development.
Classification tasks in machine learning involving more than two classes are known by the name of "multi-class classification". Performance indicators are very useful when the aim is to evaluate and compare different classification models or machine learning techniques. Many metrics come in handy to test the ability of a multi-class classifier. Those metrics turn out to be useful at different stage of the development process, e.g. comparing the performance of two different models or analysing the behaviour of the same model by tuning different parameters. In this white paper we review a list of the most promising multi-class metrics, we highlight their advantages and disadvantages and show their possible usages during the development of a classification model.