SUBCLU is an algorithm for clustering high-dimensional data by Karin Kailing, Hans-Peter Kriegel and Peer Kröger. It is a subspace clustering algorithm that builds on the density-based clustering algorithm DBSCAN. SUBCLU can find clusters in axis-parallel subspaces, and uses a bottom-up, greedy strategy to remain efficient.
SUBCLU uses a monotonicity criteria: if a cluster is found in a subspace , then each subspace also contains a cluster. However, a cluster in subspace is not necessarily a cluster in , since clusters are required to be maximal, and more objects might be contained in the cluster in that contains . However, a density-connected set in a subspace is also a density-connected set in .