Clustering groups data items by similarities, differences, or hidden structures without relying on labeled outputs or predefined categories. It is a central use of unsupervised learning for finding patterns in unorganized or unlabeled data. section 3.6
Customer segmentation
A retailer can cluster customers by purchasing behavior, revealing groups such as budget-conscious shoppers, luxury enthusiasts, and occasional buyers. These segments can guide marketing, product recommendations, and inventory planning. section 3.6
Clustering can support several practical forms of pattern discovery:
- Group cities by population size to help identify patterns and trends. section 10.5.3
- Surface unusual structures in financial activity, including possible money-laundering patterns hidden among legitimate transactions. section 3.6

















