Controlled Vocabulary & Knowledge Org. Systems

LIS 653

Starr Hoffman

How it All Fits Together

Record(representat

ion of bibliographi

c information)

Code (rules:

AACR2, RDA)

Encoding (MARC, XML)

Authority control

(standardized author name:

J. R. R. Tolkien)

Structure (ISBD,

XML)

Subject headings (LCSH, Sears,

AAT)

Classification

(shelving: LC, Dewey)

Model (FRBR, trad.

model)

Record is displayed in an OPAC, online database, etc.

Format(MARC,

Dublin Core)

Core Concepts of Controlled Vocabularies

Organized list of terms Words and/or phrases

Used to label content Used to find content Terms may be:

Hierarchically structured Relational Something in-between (BT, NT, RT)

CVs attempt to resolve problems…

User language doesn’t match language of the document they’re seeking

User wants to find all resources on a given topic

User wants to find out what language a system/organization uses to describe a given concept

Approaches…

Pre-coordinate: subdivided terms create compounded, complex concepts (LCSH)

Post-coordinate: single concepts, basic terms (that can be combined later during the search process)

Able to assign multiple subject terms regardless of the above method used

Hierarchical vs. more complex/subtle relationships

Finite, limited (thesaurus) vs. evolving, broad (LCSH)

Controlled vs. uncontrolled (tags, concept maps)

Types of Controlled Vocabularies

Thesaurus: specific subject domain (Getty’s AAT)

Subject heading list: library context, describe “aboutness” of items in catalog records (LCSH, Sears)

Classification scheme: library or other context (taxonomy), descriptor to group like items together (LCC, DDC)

Authority file: list of names of individuals or geographic places (LC Authority Files)

Keyword list, Tag cloud: often user-defined/community-defined, used to group similar content in social media or other websites

Website categories (aka taxonomy): tree-like hierarchical structure, similar to classification (w/o notation / call #)

Concept Map (aka ontology): visual representation of relationship between concepts, relays meaning (semantics)

Arrangement of CVs/KOSsCV type Structure Pre- or post-

coordinateAbout

Thesaurus Alphabetical & Systematic (2 parts)

Post-coordinate Narrow scope: one subject domain; cross-references, related terms, synonyms, etc.

Subject heading list

Alphabetical &/or Systematic

Both pre-coordinate & post-coordinate

Broad general focus; cross-references, related terms, synonyms, etc.

Classification scheme

Systematic Pre-coordinate Often hierarchical, expressed in notation (code) rather than in words

Authority file Alphabetical Post-coordinate Lists of names: geographies, individuals

Keyword list, Tag cloud

Alphabetical (& tag cloud as size-systematic)

Usually post-coordinate, may be either

User-created; usually does not identify synonyms, hierarchy, relationships between terms

Website categories (taxonomy)

Alphabetical & Systematic

Hierarchical (tree structure)

Concept map (ontology)

Visual arrangement of relationships between concepts (Systematic)

(no preferred terms, so does not apply)

Graphic representation of concepts in a subject domain; often complex relationships (not just hierarchical)

Some Issues When Constructing CVs…

Word form (plural vs. singular) Cat vs. Cats

Sequence & form for phrases Energy conservation vs…. Conservation of energy resources

Homographs & homophones Mercury: planet, metal, Roman god, car Fowl vs. foul

Qualifiers Mercury (planet) Mercury (Roman deity)

Some Issues When Constructing CVs…

Abbreviations, acronyms AIDS vs. Acquired Immune Deficiency Syndrome

Popular vs. technical terms Cancer vs. Neoplasms

Precoordinate (subdivision) vs. Postcoordinate

Merchant marine—officers Versus... Merchant marine Officers

Thesaurus Abbreviations TT: top term

broadest term in hierarchy BT: broader term NT: narrower term RT: related term USE: use X

points to a preferred term (X) UF: “use for”

the preferred term SN: scope note

describes meaning of the term meaning

Keywords Often chosen by authors of works

(uncontrolled, miss synonyms or related concepts)

Info retrieval system may use combination of keywords & assessing document’s full text (databases)

Usually not connected to synonyms or hierarchy of terms

Tag Clouds, Folksonomies

Tag Cloud Issues…

science fictionScienceFiction

scifisci-fi SF

Hard SF

time travel

books I read in high school

Dystopian futures with strong female leads

YA distopia

cyborgs

YA dystopia

robots

androids

AI

Artificial intelligence

Scifi-lite

stuff

Website Categories

Concept Map

Concept Map

Literati database…http://clio.columbia.edu/catalog/9356779

More Examples

Linked lists of controlled vocabularies:http://geekyartistlibrarian.pbworks.com/w/page/88627766/PrattLIS653_ControlledVocabularies