How does DBSCAN detect noise points?

Updated May 15, 2026

Short answer

DBSCAN labels points that do not belong to any dense region as noise.

Deep explanation

Points not reachable within epsilon neighborhood of core points are marked as noise (-1 label).

Real-world example

Detecting anomalies in fraud detection systems.

Common mistakes

Confusing noise with small clusters.

Follow-up questions

Can DBSCAN handle outliers well?

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