The Clustering component is a Solr contrib module that provides an extension point to integrate a clustering engine. Clustering
is a technology that groups documents into similar clusters, using sophisticated statistical techniques. Each cluster is identified by a few words that were used to distinguish the documents in that cluster from the other clusters. As with the
MoreLikeThis component which also uses statistical techniques, the quality of the results is hit or miss.
The primary means of navigation / discovery of your data should generally be search and faceting. For so-called un-structured text use cases, there are, by definition, few attributes to facet on. Clustering search results and presenting tag-clouds ...