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Explore the challenges with Library of Congress Subject Headings and the benefits of keyword searching, alongside solutions for improved subject analysis in library cataloging. Delve into controlled vocabulary, synonyms, homographs, and the impact of language on keyword searching success.
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Are LCSH still effective? Why not use keyword searching instead? Presented by Carol Bradsher October 29, 2004
Problems • What are the problems with subject analysis in general and the Library of Congress Subject Headings, specifically?
Survey says… • Complexity, which impacts ability of catalogers to assign and general public to use • 75% of users do not understand; • 50% of librarians don’t either; • No guidance on determining “aboutness” • Inconsistency of heading assignment, influenced by subjectivity, cultural biases, differing perspectives of catalogers
Aboutness… • Assigning subject headings is an art, not a science • Cataloging standards favor the known item
This boils down to… • Subject search is the most widely used (50% of catalog searches are subject searches) and the most frustrating one for information seekers WHAT THE HELL DO YOU MEAN NO MATCH FOUND?
Discussion point • What are the advantages of controlled vocabulary? • Advantages of keyword searching? • Disadvantages of keyword?
Advantages of controlled vocabulary • Can handle variations in language and terminology • Synonyms • Homographs • Can combine terms into phrases, relate phrases to one another • Cross reference structure to direct users to valid terms
Advantages of keyword • Greater recall • Requires less knowledge to search • Can access entire bibliographic record, table of contents, summary • pre-coordinate indexing vs. post-coordinate, which allows multiple headings to be accessed (Dancers AND Musicians)
Disadvantages of keyword Success of keyword searching depends on 2 assumptions: • Authors writing about the same concepts will use the same words in their writings; • Searchers will be able to guess what words those authors used for the concepts
Language—the biggest obstacle for keyword searching • Synonyms • Homographs • Determining the meaning of words
Synonyms • Words can have the same meaning, or not, e.g. • Attire, dress, clothing • Various styles of dress • She is wearing a lovely dress
Synonyms • Singular vs. plural form doesn’t always have the same meaning • Apple (fruit and/or tree) • Apples (fruit only) • Art (visual art) • Arts (various subdisciplines including visual, literature, performing)
What about synonym lists? • not large or general enough • Implemented in small and specialized domains • No knowledge of adjectives and nouns and which kind of words could be used together to make a phrase • Aircraft = planes • Big = large • Big aircraft = large planes
Homographs • Words that look the same but have different meanings: • Mercury: liquid metal, planet, car, Roman God or Freddie • Bridge: structure, dental device, card game, musical conveyance
Keyword’s biggest weakness • “Subject analysis so far has defied automatic techniques such as word counting; only a human can attach words to a concept that is the subject of a document but is never explicitly named in that document.” -- Arlene Taylor
What’s the solution? • Disadvantages to both controlled vocabulary and keyword, what do we do? • Throw out LCSH • Throw out keyword • Start over?
Suggested solutions • Hildreth: keep LCSH, change automated systems so they search more intelligently
Index worthy books • Paul Frantz: expand scope of EGLI and use it to address content of nonfiction books contained in the Book Review Digest (ca. 5000 titles) • Could be accomplished by 3 or 4 catalogers doing 7-8 books per day
Standardize order of subdivisions in LCSH • Study by Karen Drabenstott (1998) on understanding subject headings • Endorses recommendation of Subject Subdivision conference (1991) • Simplify cataloging and save money • No training needed on the ordering of subdivisions • Staff time saved in verification • Makes machine verification of headings possible
FAST • OCLC research project, Faceted Application of Subject Terminology • Derived from LCSH, but simpler syntax • Intended audience: web resources
FAST background • Response to an ALCTS subcommittee recommendation for subject analysis of web resources • Built on LCSH to take advantage of: • Existing schema with strong history and LC support • rich terminology • Extensive use • Post-coordinate searching • Dogs AND Housing
Mechanics 6 facets at this point: • Topical (includes topical subdivisions) • Geographic • Form • Period • Personal name • Corporate name (rest to be added later)
New rules • Everybody in the pool! • All topical headings and their subdivisions in the Authority File as strings • West Side Story for subdivisions • stick with your own kind, topical headings subdivided by topical sbd, geographic headings by geographic sbd, etc. • Back to the future • Geographic headings formulated in indirect order, e.g. Ohio—Columbus; Ohio—Columbus—German Village
LCSH: 650 Authority files (Information retrieval) $z Italy $z Florence $v Congresses FAST: Topical: Authority file (Information retrieval) Geographic: Italy $z Florence Form: Congresses examples
Summary • What’s our purpose today?