What is hierarchical clustering?

Updated May 15, 2026

Short answer

Hierarchical clustering builds nested clusters in a tree structure.

Deep explanation

It can be agglomerative or divisive, merging or splitting clusters iteratively.

Real-world example

Organizing documents into topic hierarchies.

Common mistakes

  • Assuming it scales well to large datasets.

Follow-up questions

  • What is dendrogram?
  • What are linkage methods?

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