HIERDENC
Clustering of categorical data sets with locality-sensitive hashing
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Information needed for clustering purposes, such as the most significant pairwise object similarities and density-based similarities are also stored in tables.
An early version of the fast database-based retrieval of nearest neighbors and clustering in large categorical datasets was published in:
Bill Andreopoulos, Aijun An, Xiaogang Wang, Dirk Labudde. Efficient Layered Density-based Clustering of Categorical Data. Elsevier Journal of Biomedical Informatics, 2009.