chapter  1
An Introduction to Cluster Analysis
ByCharu C. Aggarwal
Pages 28

The problem of data clustering has been widely studied in the data mining and machine learning literature because of its numerous applications to summarization, learning, segmentation, and target marketing [46, 47, 52]. In the absence of specific labeled information, clustering can be considered a concise model of the data which can be interpreted in the sense of either a summary or a generative model. The basic problem of clustering may be stated as follows: