Looking for significant connections: An overview on classification

Classification is a very general task that enables the recognition of identity, compliance, and belonging by identifying similarities among samples belonging to a given category and/or contrasting different categories based on salient features. Classification has many applications, including food authenticity, material quality control, forensic assessments, evaluating disease states, and contamination evaluation in environmental studies. This explains why so many chemometric methods have been developed over the years to accomplish classification. Nevertheless, despite the broad use of classification, there is still a need to revise and systematize the diverse tools, linking them to the specific research questions typical of different application contexts. The chapter will introduce the concept of classification, point out the areas where it is wise to apply it, illustrate the main classification approaches, such as class modeling and discriminant analysis, as well as provide some guidelines for practitioners.