| By Heather Hedden |
Benefits of a Thesaurus
Most of Gale’s products, especially those on the InfoTrac platform, make use of the Gale Master Thesaurus to index a wide variety of content types (articles, reference book chapters, images, audio, video, etc.) with Subjects. The Subject indexing provides greater precision and recall in retrieving comprehensive, accurate results than by keyword search alone. Users may search on Subjects, but even when they start with a keyword search, they can limit their results by Subjects that have been indexed to the records and which are displayed in the margin. Furthermore, when users enter a search word or phrase, if that matches even the synonyms of a Subject, InfoTrac offers the user the option of selecting the corresponding Subject to search on.
A thesaurus not only aids the end-users, but also supports indexers, so that multiple indexers—indexing content from multiple sources—index the same concepts consistently with the same terms.
A thesaurus of Subjects is not just a list of terms but is structured with relationships of broader term, narrower term, and related term—and there are also variants/synonyms, which are called “nonpreferred terms” in a thesaurus, to redirect users to the approved term name. A thesaurus is a kind of taxonomy, which is a more generic list of terms that may have hierarchical relationships but does not necessarily have related-term relationships or synonyms. A thesaurus, such as Gale’s, unlike other taxonomies, is also created according to best practices or standards, namely ANSI/NISO Z39.19-2005 Guidelines for the Construction, Format, and Management of Monolingual Controlled Vocabularies.
Benefits of Licensing a Thesaurus
The use of a thesaurus is not limited to subscription research databases, such as Gale’s. A library may have its own special collection to index, or a librarian may be asked to index a local or specialized periodical publication, in which case a thesaurus would be very helpful. If you were to index internal content for employees, a customized taxonomy or thesaurus should be created, but if you index content, such as published articles, for wider access (the public or students) than licensing an existing thesaurus will save a lot of time and effort and will also be of high quality.
Although free and open source taxonomies and thesauri exist for license, such licenses tend to be restrictive, prohibiting adaptation or commercial reuse. Gale’s license agreements permit adaptation, publishing, distribution, and creation of derivative works. That means you can edit a thesaurus you license from Gale, or even just use a Gale thesaurus as a basis for your own thesaurus, and you can use it commercially.
Gale Thesauri for License
Gale offers its Master Thesaurus (a total of over 60,000 preferred terms) as subject-category subsets to license. There are 71 individual sub-thesauri for license, which range in size from 47 terms in the small Public Relations thesaurus to 21,260 for the Science thesaurus. Most thesauri have several hundred or a couple thousand preferred terms. Most thesauri are specialized, but Gale also offers six larger thesauri, which are aggregates of several small thesauri. These are Business (6,930), Health and Medicine (12,400), Humanities (7,430), Science (21,250), Social Sciences (13,680), and Technology (10,010). Numbers are estimates of preferred terms, which are constantly being added and updated. There is also a Person Type thesaurus of 4,420 terms and a Products/Services thesaurus of 13,170 terms. Gale’s extensive vocabularies of names/proper nouns are not available to license.
The Gale thesauri, built to ANSI/NISO Z39.19-2015 standards, have hierarchical (broader term/narrower term) relationships, associative (related term) relationships, and equivalence (preferred /nonpreferred term or use/used from) relationships. Many terms also have explanatory notes (scope notes) for terms. They are continually maintained by a team of professional thesaurus editors (of which I am one).
As thesauri, rather than hierarchical taxonomies, they are not structured in a limited number of neat hierarchies for full browsing by end-users, and some terms do not have any broader terms. Rather, the thesaural relationships guide both end-users and indexers to find the best term.
The thesauri are available in various electronic form for download, which you can then import into your own content management system or other systems.
Find Out More
Information about licensing Gale thesauri >>
Fill out the contact form, and Gale’s Business Development Manager for Licensing and Strategic Partnerships will respond. You can obtain a sample from a thesaurus, after signing a non-disclosure agreement, before making a decision.
I will be giving a webinar on the topic of licensing controlled vocabularies through the SLA Taxonomy Division on Wednesday, February 20, 2019, at 12:00 pm EST, which will include information gathered from a Taxonomy Licensing Interest Survey I have created. Fill out the survey if you want to share your perspectives.
Heather Hedden is a senior vocabulary editor at Gale, where she edits the Master Thesaurus and other metadata for the indexing and retrieval of Gale research database content. She presents on taxonomies and thesauri at conferences, including the upcoming pre-conference taxonomies course at SLA 2019. Heather is currently co-chair of the working group to revise the NISO index standard, is author of The Accidental Taxonomist (Information Today Inc., 2010, 2016), and blogs at http://accidental-taxonomist.blogspot.com/