[1] Examples include diagnostic tests, identifying spam emails and deciding whether to give someone a driving license.
It may encompass both classification and the creation of classes, as for example in 'the task of categorizing pages in Wikipedia'; this overall activity is listed under taxonomy.
Classification is a part of many different kinds of activities and is studied from many different points of view including medicine, philosophy,[2] law, anthropology, biology, taxonomy, cognition, communications, knowledge organization, psychology, statistics, machine learning, economics and mathematics.
[3] Unlike in decision theory, it is assumed that a classifier repeats the classification task over and over.
The Gini coefficient and KS statistic are widely used in the credit scoring industry.