Clustering is a technique used to group similar objects (close in terms of distance) together in the same group (cluster). Unlike supervised learning methods (for example, classification and regression) covered in the previous chapters, a clustering analysis does not use any label information, but simply uses the similarity between data features to group them into clusters.
Clustering can be widely adapted in the analysis of businesses. For example, a marketing department can use clustering to segment customers by personal attributes. As a result of this, different marketing campaigns targeting various types of customers can be designed.
The four most common types of clustering methods are hierarchical clustering, k-means clustering, model-based clustering, and density-based clustering:
- Hierarchical clustering: This creates a hierarchy of clusters, and presents the...