Hard clustering assigns each object decisively to one cluster when its membership is considered clear. It supports segmentation, pattern discovery, and data understanding without a target variable. section 2.2 section 2.10
Distinguish hard clustering from related choices:
- Assigns an object to one cluster, unlike soft or fuzzy clustering, which allows multiple memberships and likelihood scores. section 2.2 section 5.5
- Includes methods such as k-means, hierarchical clustering, and DBSCAN, although these algorithms use different similarity and grouping methodologies. section 2.2 section 2.10
- Depends on modeling choices such as attributes and distance measures, which can change the resulting clusters. section 2.2
K-means assignment
K-means provides a classic hard-clustering example: it creates nonoverlapping clusters by assigning each data point to the nearest center after specifying the number of clusters. section 2.10 section 5.5

