— Bella Hass Weinberg
All About Facets and Controlled Vocabularies (series introduction)
1. What is a Controlled Vocabulary?
2. Creating a Controlled Vocabulary
3. Synonym Rings and Authority Files
Introduction
“There is a singular lack of vocabulary control in the field of controlled vocabularies,” Bella Hass Weinberg, professor of library science at St. John’s University in New York, is fond of saying.
To help you cut through the maze of verbiage often found in this field, we have created a glossary of terms.
The glossary reflects our usage of terms in the articles of this series. But this glossary is more than just a list of terms. We wanted it to serve as an illustration of what a controlled vocabulary looks like (we are fond of killing multiple birds with multiple stones).
Accordingly, the glossary is itself a controlled vocabulary, more specifically a thesaurus. So you will find all of the standard features of any thesaurus: broader, narrower, and variant term indicators, as well as scope notes. In this case, however, the scope notes provide the definition of the particular glossary term being presented.
Glosso-Thesaurus
The following standard abbreviations are used in the glosso-thesaurus.
BT = Broader Term
NT = Narrower Term
RT = Related Term (“See also”)
SN = Scope Note
UF = Used For
USE = “See” (Refers reader from variant term to vocabulary term.)
- USE Variant Term
- SN The connection between related vocabulary terms. That is, related terms are connected through an associative relationship.
BT Term Relationship
RT Equivalence Relationship
Hierarchical Relationship
Related Term
- SN A flat (non-hierarchical) list containing preferred terms. May include variant terms. Essentially, an authority file is a synonym ring with the preferred term identified for each concept.
- SN The superordinate word in an inclusion or hierarchical relationship. A class or category term. Abbreviated in displays as “BT.” The inversion of broader term is narrower term. For example, “shoe” is a broader term than “running shoe.” Broader terms are sometimes referred to as “parent” terms.
UF Parent Term
RT Hierarchical Relationship
Narrower Term
Related Term
- SN An exercise that can be used to help create a controlled vocabulary. In a card sort, users are asked to group cards into like categories or to name categories of like items. Card sorting can be used to compile lists of variant terms or to verify the relationships in a hierarchy. For additional information, see Card-Based Classification Evaluation by Donna Maurer or the IAWiki page on card sorting.
- USE Narrower Term
- SN A subset of natural language that is used to tag documents and then to find content through navigation or search. Use of a controlled vocabulary increases consistency in tagging and can help match users’ natural language with preferred terms. Abbreviated as “CV.”
Controlled vocabularies exhibit the following relationships:
Synonym ring
+ Preferred terms =
Authority file
+ Broader and narrower terms =
Taxonomy
+ Related terms =
Thesaurus
NT Authority File
Faceted Classification
Synonym Equivalence List
Synonym Ring
Taxonomy
Thesaurus
- USE Variant Term
- SN The connection between terms in a synonym ring, or between preferred terms and variant terms. Terms that exhibit an equivalence relationship refer to the same concept. For example, “cat” and “feline” are often considered as being equivalent.
BT Term Relationship
RT Associative Relationship
Hierarchical Relationship
Variant Term
- SN The range of concept coverage of vocabulary terms in a controlled vocabulary. If the vocabulary terms cover all of the concepts included in the content under consideration, then the controlled vocabulary is exhaustive.
RT Specificity
- SN A fundamental category by which an object or concept may be described. For example, a child’s ball may be described using the facets of size, weight, shape, color, texture, material and price.
- SN The process of analyzing content to determine appropriate facets and vocabulary term relationships, using “one characteristic of division at a time, to produce homogeneous, mutually-exclusive groups.” *
RT Facet
Faceted Classification
* Aitchison, Jean, Alan Gilchrist, and David Bawden (2002). Thesaurus Construction and Use: A Practical Manual. 4th ed. Chicago: Fitzroy-Dearborn, pg. 70.
- SN A controlled vocabulary that divides vocabulary terms into facets.
- A method of vocabulary development in which users are asked to “name all the [x] you know.” Free listing can identify core terms in a controlled vocabulary, as well as variant terms. For additional information, see Beyond cardsorting: Free-listing methods to explore user categorizations by Rashmi Sinha.
- SN The level of specificity with which content is described. The more granular, the more specific.
RT Specificity
- SN A collection of vocabulary terms that show levels of superordination and subordination. Hierarchies comprise broader terms and narrower terms. Hierarchies may be testing using card sorting.
- SN The connection between broader and narrower terms in a taxonomy or thesaurus.
BT Term Relationship
RT Associative Relationship
Broader Term
Equivalence Relationship
Narrower Term
- SN The inclusion of a vocabulary term in a controlled vocabulary based on its appearance in one or more content items. For example, a medical text may use the term “oncology.” Based on literary warrant, that term would be included in the controlled vocabulary even though the general public uses the term “cancer.”
- SN The subordinate word in an inclusion or hierarchical relationship. A member or part. Abbreviated in displays at “NT.” For example, “running shoe” is a narrower term than “shoe.” Narrower terms are sometimes referred to as “child” terms.The inversion of narrower term is broader term.
UF Child Term
RT Broader Term
Hierarchical Relationship
Related Term
- SN Language as it is spoken; language in everyday use.
RT Controlled Vocabulary
User Warrant
USE Variant Term
- USE Broader Term
- SN A hierarchy in which some vocabulary terms have more than one broader term. For example, “Rome” might be a narrower term under both “European capitals” and “Italian cities” in a geographic vocabulary.
- SN A ratio that measures the success of a search. Precision is defined mathematically as the number of relevant items returned by a search divided by the total number of items returned by the search. Thus, a search that returned only relevant items would have a precision of 1.0.
Precision usually has an inverse relationship to recall. That is, increasing the precision of a search usually decreases the recall. Precision can be increased by increasing the specificity of vocabulary terms. For more information, see:
IAWiki: “Recall vs. Precision”
Ongoing: “On Search: Precision and Recall”
- SN The vocabulary term in a controlled vocabulary used to tag content.
- SN A ratio that measures the success of a search. Recall is defined mathematically as the number of relevant items returned by a search divided by the total number of relevant items in the collection. Thus, a search that returned all the relevant items in a collection would have a recall of 1.0.
Recall can be increased by the use of synonym rings and variant terms. Recall usually has an inverse relationship to precision. That is, increasing the recall of a search usually decreases the precision. For more information, see:
IAWiki: “Recall vs. Precision”
Ongoing: “On Search: Precision and Recall”
- SN Vocabulary terms in a controlled vocabulary that are closely related. That is, they refer to closely related concepts. Abbreviated in displays as “RT.” Related terms may, for example, exhibit the following relationships:
field of study/objects studied
operation/agent
action/product of action
concepts/properties
agent/counter-agent
concept/opposite
For additional information, see the section in associative relationships in What is A Controlled Vocabulary? by Karl Fast, Mike Steckel and Fred Leise.
UF “See Also” Term
RT Associative Relationship
- SN (1) A definition of a preferred term in a controlled vocabulary. (2) An indication of restrictions in meaning or other clarification needed for the proper use of the preferred term. Abbreviated in displays as “SN.” Examples of scope notes are provided throughout this glossary.
- USE Related Term
- SN The exactness with which a vocabulary term covers a concept. Thus, in considering the concept “dog,” the term “canine” is more specific than “animal.” Increasing specificity of vocabulary terms increases precision and granularity, but may decrease recall.
- SN A synonym ring or an authority file.
- SN One of the simplest of controlled vocabularies. Includes only a list of equivalent terms. When one of the terms is searched, the synonym ring returns results as if the complete set of terms was searched.
BT Controlled Vocabulary
RT Equivalence Relationship
Synonym Equivalence List
- SN A controlled vocabulary, the preferred terms of which are all connected in a hierarchy or polyhierarchy. Terms in a taxonomy may exhibit equivalence or hierarchical relationships.
BT Controlled Vocabulary
RT Hierarchical Relationship
Hierarchy
Polyhierarchy
- USE Vocabulary Term
- SN The type of association between vocabulary terms. Terms may be broader, narrower, related or variant, exhibiting hierarchical, associative or equivalence relationships.
NT Associative Relationship
Equivalence Relationship
Hierarchical Relationship
RT Broader Term
Narrower Term
Related Term
Variant Term
- SN A controlled vocabulary that indicates preferred terms and variant terms. In addition to the equivalence relationship, vocabulary terms in a thesaurus exhibit both hierarchical and associative relationships. These three relationships are called “standard thesaural relationships.” Thesauri are usually considered the most complex of controlled vocabularies.
BT Controlled Vocabulary
RT Associative Relationship
Equivalence Relationship
Hierarchical Relationship
- SN The inclusion of a vocabulary term in a controlled vocabulary based on use by users. Such terms can be identified through search log analysis or free listing.
- SN A vocabulary term that means nearly the same thing as a preferred term. Variant terms are used in the controlled vocabulary to provide entry terms that lead to preferred terms. Variant terms may include synonyms, lexical variants, quasi-synonyms and abbreviations. Variant terms are sometimes referred to as “entry terms.” The collection of all variant terms may be referred to as the “entry vocabulary.”
UF Alternate Term
Entry Term
Non-preferred Term
RT Equivalence Relationship
Preferred Term
- SN A word or phrase in a controlled vocabulary. It may be a preferred term or variant term. Vocabulary terms may exhibit several types of term relationships.
UF Term
NT Preferred Term
Variant Term
Bibliography
References
Fred Leise, president of ContextualAnalysis, LLC, is an information architecture consultant providing services in the areas of content analysis and organization, user experience design, taxonomy and thesaurus creation, and website and back-of-book indexing.
Mike Steckel is an Information Architect/Technical Librarian for International SEMATECH in Austin, TX.
October 29, 2003 at 2:53 pm
To quote a colleague, this article is “painfully elegant.” I love the idea of the CV glossary being a CV itself.
November 5, 2003 at 9:00 pm
Hey, where’s “aboutness” ??
November 10, 2003 at 1:15 pm
I like this “Glosso-Thesaurus.” Very clever. Nice addition to your helpful series on controlled vocabularies and faceted classification.
November 10, 2004 at 10:58 am
Didn’t Glosso-Thesaurus fight Godzilla in “Giant Monster Gamera”?
October 3, 2005 at 2:57 am
My opinion on facets is different. I think a facet is a way in which a user may look at the object. This means that a facet says as much about the user as it says something about the object. I think a facet is the question a user may ask about the object. I think creating facets requires user analysis. I know my opinion is different from what I hear from others.
If you mention “aboutness”, I mention “basic-levelness”.
January 6, 2006 at 5:22 am
Please note that the authors of this article are Karl Fast, Mike Steckel and Fred Leise.