Search Components Online

WordNet: An Open Source Thesaurus

The fine folks at Princeton have an online database of synonyms that can also be used with your own code.  This is pretty amazing, given how carefully guarded most of the traditional thesaurus providers have been.

See the main site, the very generous license (free for commercial use and modification under reasonable conditions), doc, stats and download.

Of course for a search application you'll need to actually do something with it.  There is a WordNet analyzer listed in the Lucene sandbox, though the link is broken.  But we have it on good authority that it does work...

Here's an article on stemming and lemmatization that includes info on thesaurus based searching, among other things.

CATMaker: Summarization Tool for Medical Text

CATMaker is an interesting tool for medical text.  It helps generate a summary of a case and a "bottom line" assessment.
http://www.cebm.net/index.aspx?o=1216

It's produced by the Center for Evidence Based Based Medicine (CEBM).  It might be open source.

Summary tools can be very helpful when used with search engines.  They can help give a better summary in a results list, or when used at index time, give the search engine a smaller, more relevant set of text to search over.

Raritan Taxonomy Tools

Taxonomies continue to be a very popular topic.  See our Taxonomies page here on this site.

Raritan Technologies in New Jersey includes a number of products and services to taxonomy-enable your site.  From their site:

Pre-built  taxonomies allow an organization to get started quickly with a taxonomy search/navigation project. There's no need to start from scratch, use taxonomies built by classification experts. If an organization has browse capabilities or hierarchical structures, they can often be used to seed a taxonomy.

See their taxonomy page at:
http://www.raritantechnologies.com/Taxonomies.shtml