1 Languages for aboutness n Indexing languages: –Terminological tools Thesauri (CV – controlled vocabulary) Subject headings lists (CV) Authority files for named entities (people, places, structures, organizations) –Classification –Keyword lists –Natural language systems (broad interpretation)

2 Subject Analysis n What something is about? –What the content of an object is “about”? n Different methods (Wilson, 1968) –Counting (objective method) –Purposive method –Method appealing to unity –What stands out n Challenges –Non-text

3 Aboutness: How to do it! n Read the document [Intellectual reading] –look for key features –many indexers mark up the items –rarely have time to read the whole document n Determine aboutness [Conceptual analysis] n Translate aboutness into the vocabulary or scheme you are using –In general: Subject headings: 1-3 headings –Descriptors, 5-8 descriptors –Classification: 1 notation (should it only be one!?).

4 Features of indexing languages: n Involve rules and require maintenance n Can be generated via automatic, human, or auto-human processes n Different processes generally display different strengths and weaknesses.

5 Features of indexing languages: n With the exception of a few general domain tools, they are generally domain specific. –MeSH –NASA Thesaurus –Astronomy Thesaurus –ERIC thesaurus n Concepts (or concept representations) are arranged in a discernable order 

6 Language schema designs n Classified--grouping –Hierarchies and facets MeSH Browser Art and Architecture (Getty AAT) n Alphabetical -- horizontal –Verbal/Alphabetical (ordering/filing challenges)

7 Controlled Vocabulary n A list or a database of subject terms in which each concept has a preferred terms or phrase that will be used to represent it in the retrieval tool; the terms not used have references (syndetic structure), and often scope notes.

8 Thesaurus (structured thesaurus) n Lexical semantic relationships n Composed of indexing terms/descriptors n Descriptors = representations of concepts n Concepts = Units of meaning (Svenonius)

9 Thesaurus n Preferred terms n Non-preferred terms n Semantic relations between terms n How to apply terms (guidelines, rules) n Scope notes n Adding terms (How to produce terms that are not listed explicitly in the thesaurus)

10 Preferred Terms n Control form of the term Spelling, grammatical form Theatre / Theater MLA / Modern language association n Choose preferred term between synonyms Brain cancer or Brain Neoplasms?

11 Common thesaural identifiers n SN Scope Note –Instruction, e.g. don’t invert phrases n USE Use (another term in preference to this one) n UF Used For n BT Broader Term n NT Narrower Term n RT Related Term

12 Semantic Relationships n Hierarchy n Equivalence n Association

13 Hierarchies of Meaning ‘Glass’ ‘Beer Glass’ ‘Wine Glass’ ‘Red wine glass’ ‘White wine glass’ From: Controlled Vocabularies/ Paul Miller Interoperability Focus UKOLN

14 Hierarchy n Level of generality – both preferred terms n BT (broader term) –Robins BT Birds n NT (narrower term) –Birds NT Robins –Inheritance, very specific rules

15 Equivalence n When two or more terms represent the same concept n One is the preferred term (descriptor), where all the information is collected n The other is the non-preferred and helps the user to find the appropriate term

16 Equivalence n Non-preferred term USE Preferred term –Nuclear Power USE Nuclear Energy –Periodicals USE Serials n Preferred term UF (used for) Non-preferred term –Nuclear Energy UF Nuclear Power –Serials UF Periodicals

17 Association n One preferred term is related to another preferred term n Non-hierarchical n “See also” function n In any large thesaurus, a significant umber of terms will mean similar things or cover related areas, without necessarily being synonyms or fitting into a defined hierarchy

18 Association n Related Terms (RT) can be used to show these links within the thesaurus –Bed RT Bedding –Paint Brushes RT Painting –Vandalism RT Hostility –Programming RT Software

19 Thesauri Guides n National Information Standards Organization. (1993). Guidelines for the construction, format, and management of monolingual thesauri. ANSI/NISO Z Bethesda, MD: NISO Press.[SILS reference Z695.N or 19.pdf] 19.pdf n Aitchison, Jean & Gilchirist, Alan. Thesaurus Construction: A Practical Guide. 3 rd ed. London: Aslib, n Willpower Information Management Consultants

20 Thesauri Directory n Indexing Resources on the WWW – se1.htmhttp:// se1.htm –-- explore ASIST Thesaurus n Controlled vocabularies – n Web Compendium –

21 n Thesauri/Keywords n Created according to standards n Z39.19 (Ansi) n Single term concepts/postcoordination  “Wireless network” & “home computer”  “Terrorism” “Attacks” & “United States” n More popular in the online environment n Lend to recall n Lend to multilingual environment n Subject Heading Lists n Rules and guidelines n “Thesaurification” n multi-word concepts/pre- coordination  “Wireless home computer network”  $y Terrorism attacks $z United States n STRINGS n Lend to precision