Medical Text Indexer (MTI) (formerly the Indexing Initiative System (IIS))
From the webpage:
The MTI system consists of software for applying alternative methods of discovering MeSH headings for citation titles and abstracts and then combining them into an ordered list of recommended indexing terms. The top portion of the diagram consists of three paths, or methods, for creating a list of recommended indexing terms: MetaMap Indexing, Trigrams and PubMed Related Citations. The first two paths actually compute UMLS Metathesaurus® concepts which are passed to the Restrict to MeSH process. The results from each path are weighted and combined using the Clustering process. The system is highly parameterized not only by path weights but also by several parameters specific to the Restrict to MeSH and Clustering processes.
A prototype MTI system described below had two additional indexing methods which were removed because their results were subsumed by the three remaining methods.
Deeply interesting and relevant work to topic maps.