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Thesaurus2050//

(vocabulary control)authority list[concept term](grouping)

1975 10487519 748 310 1985

IntroductionThesaurus Treasury, CollectionA book of words and their synonymsMerriam-Websters DictionaryA book of words that are put in groups together according to connections between their meanings rather than in an alphabetical list. (Longman Dictionary of Contemporary English)e.g., Rogets Thesaurus of English Words and Phrases1957AD H. P. LuhnThesaurusBrownson1957

19591960 the Armed Services Technical Information Agency (ASTIA) produced the Thesaurus of ASTIA Descriptors1961 the American Institute of Chemical Engineers (AIChE) published the Chemical Engineering Thesaurus1964 the Engineers Joint Council (EJC) published the Thesaurus of Engineering Terms1967 Thesaurus of Engineering and Scientific Terms (TEST)

Brief History (cont.)1967 the Committee on Scientific and Technical Information (COSATI) published the first set of guidelines for thesaurus construction1970 Unesco Guidelines for the Establishment and Development f Monolingual Scientific and Technical Thesaurus1974 ANSI (American National Standards Institute) Z39.19 [a US national standard for thesaurus construction]1974 the first international standard for thesaurus construction ISO 2788

Its purposes are to promoted consistency in the indexing of documents, predominantly for postcoordinated information storage and retrieval systems, and to facilitate searching by linking entry terms with descriptors (ANSI Z39.19-1993, p. 38)Four principal purposes are served by a thesaurus:Translation. To provide a means for translating the natural language of authors, indexers, and users into a controlled vocabulary used for indexing and retrieval.Consistency. To promote consistency in the assignment of index terms.Indication of Relationships. To indicate semantic relationships among terms.Retrieval To serve as a searching aid in retrieval of documents.(ANSI Z39.19-1993, p. 1)

:Synonyms different terms representing the same conceptPolysemes a word with multiple meanings [in spoken language, polysemes are homonyms; in written language, they are homographs terms with the same spelling representing different concepts. Only the latter is relevant to thesauri.]

Vocabulary control in a thesaurus is achieved through three principal means:the delineation of the scope, or meaning, of descriptors Scope Note (SN)the linking of synonymous and nearly (quasi) synonymous terms through equivalence relationship USE and UFthe disambiguation of homographs Qualifier(Source: ANSI Z39.19-1993, p. 1)

An intrinsic feature of a thesaurus is its ability to distinguish and display the structural relationships between the terms it contains.There are two broad types of relationships within a thesaurus:Micro Level the semantic links between individual termsMacro level how the terms and their inter-relationships relate to the overall structure of the subject field(Source: J. Aitchison, A. Gilchrist, & D. Bawden. Thesaurus Construction and Use: A Practical Manual. 3rd ed. London: Aslib, 1997. P. 47)

:: the relationship between preferred and non-preferred terms where two or more terms are regarded, for indexing purposes, as referring to the same concept : this relationship shows levels of superordination and subordination. The superordinate term represents a class or whole, and the subordinate terms refer to its members or parts: the relationship is found between terms which are closely related conceptually but not hierarchically and are not members of an equivalence set. (relationship: Aitchison, Gilchrist, & Bawden, 1997, Section F)

Descriptors Preferred termsLead-in terms (Entry terms) Non-preferred termsLead-in termUSE DESCRIPTORDESCRIPTORUF Lead-in termExample: USE (preferred term) UF (non-preferred term)

Synonyms terms are virtually interchangeable or regarded as the samePopular names and scientific namesCommon nouns or scientific names, and trade namesStandard names and slang Terms originating from different cultures sharing a common language (e.g., pavements/sidewalks)Competing names for emerging concepts (e.g., metadata)Current or favored term versus outdated or deprecated term (e.g. dishwashers/washing-up machines)

Lexical variants different word forms for the same expressing, such as spelling, grammatical variation, irregular plurals, direct versus indirect order, and abbreviated formatsVariant spellings e.g., moslems/muslims; mouse/mice; colour/colorDirect and indirect form e.g, academic library vs. library, academic Abbreviations and full namese.g., ALA vs. American Library Association

Quasi-synonyms, or near-synonyms terms whose meanings are generally regarded as different in ordinary usage, but they are treated as though they are synonyms for indexing purposes.Terms having a significant overlape.g., urban areas/cities gifted people/geniusesAntonyms or terms representing different viewpoints of the same property continuume.g., dryness/wetness equality/inequality

Upward posting (generic posting) This is a technique which treats narrower terms as if they are equivalent to, rather than a species of, their broader terms. The effect is to reduce the size of the vocabulary.SOCIAL CLASSUF Elite Middle class Working class EliteUSE SOCIAL CLASS

The relationship is reciprocal and is set out in a thesaurus using the following conventions:BT (Broader Term)NT (Narrower Term)e.g.,Public LibrariesBT LibrariesLibrariesNTAcademic LibrariesChildrens LibrariesPublic Libraries

/Generic/species relationship identifies the link between a class or category and its members or species (e.g., Bird / Robin)/Whole/part relationshipSystems and organs of the body (e.g., / )Geographical location (e.g., Taipei / Ta-an District)Discipline or field of study (e.g., Chemistry / Organic chemistry)Hierarchical social structure (e.g., army and its rank system)

Instance relationship a general category of things and events, expressed by a common noun, and an individual instance of that category, the instance then forming a class of one which is represented by a proper name (e.g., SEAS / Pacific Ocean)Polyhierarchical relationships the relationship between the term and its two or more superordinate terms is said to be polyhierarchical.

NURSES HEALTH ADMINISTRATORS NT Nurse Administrators NT Nurse Administrators

NURSES ADMINISTRATORS BT Health administrators Nurses

RTThe relation is reciprocal, and is distinguished by the abbreviation RT (Related Terms)e.g.,TEACING RT Teaching aids

TEACHING AIDS RT Teaching

Terms belonging to the same category (e.g., motorcycle / bicycle)Terms belonging to different categoriesWhole-part (e.g., buildings / doors)A discipline and the objects studied (e.g., ethnography / primitive societies)An operation or process and the agent or instrument (e.g., motor racing / racing cars)An occupation and the person in that occupation (e.g., accountancy / accountants)An action and the product of the action (e.g., publishing / music scores)

Terms belonging to different categories (cont.)An action and its patient (e.g., data analysis / data)Concepts related to their properties (e.g., women / femininity)Concepts linked by causal dependence (e.g., injury / accidents)A thing or action and its counter-agent (e.g., pests / pesticides)A raw material and its product (e.g., / )An action and a property associated with it (e.g., precision measurement / accuracy)A concept and its opposite (e.g., single people / married people)

COMPETENCY BASED EDUCATION Mar. 1980CIJE: 884 RIE: 2881 GC: 330SNEducational system that emphasizes the specification, learning, and demonstrating of those competencies (knowledge, skills, behaviors) that are of central importance to a given task, activity, or career.UFConsequence Based EducationCriterion Referenced EducationOutput Oriented EducationNTCompetency Based Teacher EducationBTEducationRTAcademic StandardsAccountabilityBack to BasicsIndividualized Instruction

AlphabeticalClassifiedHierarchicalPermuted Keyword IndexGraphical

Is a thesaurus necessary?If it is, which of the followings would be a better or more suitable approach?BuyingCompilingAdaptingA very useful Web site to find information about thesaurus construction and use prepared by Willpower Information http://www.willpower.demon.co.uk/thesbibl.htm

Subject fieldType of literature/dataQuantity of literature/dataLanguage considerationsSystem usersQuestions, searchers, profilesResources available(Source: Aitchison, Gilchrist, & Bawden, 1997, Section B)

Convene a group of subject experts to decide on the scope and broad categories of terms to be included. Use existing dictionaries and thesauri to decide on the terms and their relationships. Review and organize the preliminary term set: decide on preferred terms and make Use references from the variants and synonyms; and build hierarchical and associative relationships among the preferred terms. Produce a draft thesaurus, test index and revise.

(source: http://www.asindexing.org/site/thesbuild.shtml)

Develop a group of subject experts to serve as advisors; work with them to determine the scope if it is not already set. If there is a set of representative already-indexed documents, use the index terms from this set as your preliminary term list. If not, index a set of representative documents using free language (i.e., no vocabulary control), and take this term set as your preliminary list. Build your thesaurus by reviewing and organizing these terms, using a variety of resources as aids, as in the top-down method. Refer to your subject experts on terms whose meaning or usage is unclear, and for advice on which variant or synonym to prefer (or on whether two terms really are synonyms in the field). Produce a draft thesaurus, test index, and revise. (Source: http://www.asindexing.org/site/thesbuild.shtml)

Collecting termsModifying and inventing termsChoosing preferred terms and standardizing the form of wordsEstablishing semantic relationshipsThesaurus arrangement and displayTesting and revisingThesaurus maintenanceThe American Society of Indexers provides a list of thesaurus management software -- http://www.asindexing.org/site/thessoft.shtml