Controlled Subject Vocabularies and Thesauri

1. Controlled Subject Vocabularies and Thesauri University of California, Berkeley School of Information Management and Systems SIMS 202: Information Organization and Retrieval Information Organization and Retrieval

2. Review • Controlled vocabularies • Choice of names • Form of names • Name Authority files Information Organization and Retrieval

3. Controlled Vocabularies • Vocabulary control is the attempt to provide a standardized and consistent set of terms (such as subject headings, names, classifications, etc.) with the intent of aiding the searcher in finding information. Information Organization and Retrieval

4. Name Authority Files ID:NAFL8057230 ST:p EL:n STH:a MS:c UIP:a TD:19910821174242 KRC:a NMU:a CRC:c UPN:a SBU:a SBC:a DID:n DF:05-14-80 RFE:a CSC: SRU:b SRT:n SRN:n TSS: TGA:? ROM:? MOD: VST:d 08-21-91 Other Versions: earlier 040 DLC$cDLC$dDLC$dOCoLC 053 PR6005.R517 100 10 Creasey, John 400 10 Cooke, M. E. 400 10 Cooke, Margaret,$d1908-1973 400 10 Cooper, Henry St. John,$d1908-1973 400 00 Credo,$d1908-1973 400 10 Fecamps, Elise 400 10 Gill, Patrick,$d1908-1973 400 10 Hope, Brian,$d1908-1973 400 10 Hughes, Colin,$d1908-1973 400 10 Marsden, James 400 10 Matheson, Rodney 400 10 Ranger, Ken 400 20 St. John, Henry,$d1908-1973 400 10 Wilde, Jimmy 500 10 $wnnnc$aAshe, Gordon,$d1908-1973 Different names for the same person Information Organization and Retrieval

5. Name Authority Files ID:NAFO9114111 ST:p EL:n STH:a MS:n UIP:a TD:19910817053048 KRC:a NMU:a CRC:c UPN:a SBU:a SBC:a DID:n DF:06-03-91 RFE:a CSC:c SRU:b SRT:n SRN:n TSS: TGA:? ROM:? MOD: VST:d 08-19-91 040 OCoLC$cOCoLC 100 10 Marric, J. J.,$d1908-1973 500 10 $wnnnc$aCreasey, John 663 Works by this author are entered under the name used in the item. For a listing of other names used by this author, search also under$bCrease y, John 670 OCLC 13441825: His Gideon's day, 1955$b(hdg.: Creasey, John; usage: J .J. Marric) 670 LC data base, 6/10/91$b(hdg.: Creasey, John; usage: J.J. Marric) 670 Pseuds. and nicknames dict., c1987$b(Creasey, John, 1908-1973; Britis h author; pseud.: Marric, J. J.) Information Organization and Retrieval

6. Name authority files ID:NAFL8166762 ST:p EL:n STH:a MS:c UIP:a TD:19910604053124 KRC:a NMU:a CRC:c UPN:a SBU:a SBC:a DID:n DF:08-20-81 RFE:a CSC: SRU:b SRT:n SRN:n TSS: TGA:? ROM:? MOD: VST:d 06-06-91 Other Versions: earlier 040 DLC$cDLC$dDLC$dOCoLC 100 10 Butler, William Vivian,$d1927- 400 10 Butler, W. V.$q(William Vivian),$d1927- 400 10 Marric, J. J.,$d1927- 670 His The durable desperadoes, 1973. 670 His The young detective's handbook, c1981:$bt.p. (W.V. Butler) 670 His Gideon's way, 1986:$bCIP t.p. (William Vivian Butler writing as J .J. Marric) Different people writing with the same name Information Organization and Retrieval

7. Processes of categorization underlie many of the issues having to do with information organization Categorization is messier than our computer systems would like Human categories have graded membership, consisting of family resemblances. Family resemblance is expressed in part by which subset of features are shared It is also determined by underlying understandings of the world that do not get represented in most systems Categorization Summary Information Organization and Retrieval

8. Today • Origins and Uses of Controlled Vocabularies for Information Retrieval • Types of Indexing Languages, Thesauri and Classification Systems • Process of Design and Development of Thesauri Information Organization and Retrieval

9. Origins • Very early history of content representation • Sumerian tokens and “envelopes” • Alexandria - pinakes • Indices Information Organization and Retrieval

10. Origins • Biblical Indexes and Concordances • Journal Indexes • “Information Explosion” following WWII • Cranfield Studies of indexing languages and information retrieval • Development of bibliographic databases • Index Medicus -- production and Medlars searching Information Organization and Retrieval

11. Message Message Source Encoding Decoding Destination Channel Message Message Source Encoding (writing/indexing) Storage Decoding (Retrieval/Reading) Destination Origins • Communication theory revisited • Problems with transmission of meaning Noise Information Organization and Retrieval

12. What is a “Controlled Vocabulary” • “The greatest problem of today is how to teach people to ignore the irrelevant, how to refuse to know things, before they are suffocated. For too many facts are as bad as none at all.” (W.H. Auden) • Similarly, there are too many ways of expressing or explaining the topic of a document. • Controlled vocabularies are sets of Rules for topic identification and indexing, and a THESAURUS, which consists of “lead-in vocabulary” and an limited and selective “Indexing Language” sometimes with special coding or structures. Information Organization and Retrieval

13. Storage Line Interest profiles & Queries Documents & data Information Storage and Retrieval System Rules of the game = Rules for subject indexing + Thesaurus (which consists of Lead-In Vocabulary and Indexing Language Formulating query in terms of descriptors Indexing (Descriptive and Subject) Storage of profiles Storage of Documents Store1: Profiles/ Search requests Store2: Document representations Comparison/ Matching Potentially Relevant Documents Structure of an IR System Search Line Adapted from Soergel, p. 19 Information Organization and Retrieval

14. Uses of Controlled Vocabularies • Library Subject Headings, Classification and Authority Files. • Commercial Journal Indexing Services and databases • Yahoo, and other Web classification schemes • Online and Manual Systems within organizations • SunSolve • MacArthur Information Organization and Retrieval

15. Types of Indexing Languages • Uncontrolled Keyword Indexing • Indexing Languages • Controlled, but not structured • Thesauri • Controlled and Structured • Classification Systems • Controlled, Structured, and Coded • Faceted Classification Systems Information Organization and Retrieval

16. Indexing Languages • An index is a systematic guide designed to indicate topics or features of documents in order to facilitate retrieval of documents or parts of documents. • An Indexing languageis the set of terms used in an index to represent topics or features of documents, and the rules for combining or using those terms. Information Organization and Retrieval

17. Indexing Languages • Library of Congress Subject Headings • Yellow Pages Topics • Wilson Indexes (“Reader’s Guide”) Information Organization and Retrieval

18. Thesauri • A Thesaurus is a collection of selected vocabulary (preferred terms or descriptors) with links among Synonymous, Equivalent, Broader, Narrower and other Related Terms Information Organization and Retrieval

19. Thesauri (cont.) • National and International Standards for Thesauri • ANSI/NISO z39.19--1994 -- American National Standard Guidelines for the Construction, Format and Management of Monolingual Thesauri • ANSI/NISO Draft Standard Z39.4-199x -- American National Standard Guidelines for Indexes in Information Retrieval • ISO 2788 -- Documentation -- Guidelines for the establishment and development of monolingual thesauri • ISO 5964-- Documentation -- Guidelines for the establishment and development of multilingual thesauri Information Organization and Retrieval

20. Thesauri (cont.) • Examples: • The ERIC Thesaurus of Descriptors • The Art and Architecture Thesaurus • The Medical Subject Headings (MESH) of the National Library of Medicine Information Organization and Retrieval

21. Classification Systems • A classification system is an indexing language often based on a broad ordering of topical areas. Thesauri and classification systems both use this broad ordering and maintain a structure of broader, narrower, and related topics. Classification schemes commonly use a coded notation for representing a topic and it’s place in relation to other terms. Information Organization and Retrieval

22. Classification Systems (cont.) • Examples: • The Library of Congress Classification System • The Dewey Decimal Classification System • The ACM Computing Reviews Categories • The American Mathematical Society Classification System Information Organization and Retrieval

23. Automatic Indexing and Classification • Automatic indexing is typically the simple deriving of keywords from a document and providing access to all of those words. • More complex Automatic Indexing Systems attempt to select controlled vocabulary terms based on terms in the document. • Automatic classification attempts to automatically group similar documents using either: • A fully automatic clustering method. • An established classification scheme and set of documents already indexed by that scheme. Information Organization and Retrieval

24. Clustering Aglomerative methods Doc Doc Doc Doc Doc Doc Doc Doc Information Organization and Retrieval

25. Automatic Class Assignment Doc Doc Doc Doc Search Engine Doc Doc Doc 1. Search using document contents 2. Obtain ranked list 3. Assign document to N categories ranked over theshold. Information Organization and Retrieval

26. Development of a Thesaurus • Term Selection. • Merging and Development of Concept Classes. • Definition of Broad Subject Fields and Subfields. • Development of Classificatory structure • Review, Testing, Application, Revision. Information Organization and Retrieval

27. Select sources for the collection of terms. Prearranged Sources Open-ended Sources Assign codes to each source. Selection of terms For part of pre-arranged and for all open-ended sources Enter terms into database with all information. 1. Preliminary Term Selection Information Organization and Retrieval

28. Sort Term DB into alphabetical order. First Round: Merge information for Identical terms -- possibly pulling info from additional sources. Second Round: Merge synonyms or terms in the same concept class. 2. Merging and Development of Concept Classes Information Organization and Retrieval

29. Define Broad Subject fields and sort terms into these broad fields Define subfields within each broad field and sort terms into these subfields. Work out the detailed structure Select Preferred Terms Merge information for terms in the same concept class Repeat these steps for each subfield within a broad field and for each broad field Until all terms have been consolidated and preferred terms selected 3. Definition of Broad Subject Fields and Subfields Information Organization and Retrieval

30. Produce preliminary version of classified index and update the working database. Improve classificatory structure Reality check: produce and distribute a version of the classified index. Distribute to users/experts. 4. Development of Classificatory Structure Information Organization and Retrieval

31. Review Testing Application Revision 5. Final Stages Information Organization and Retrieval

32. Review • Discuss classified index with users/experts. • Select descriptors and checklist descriptors. • Assign Notational Symbols • Produce Main Thesaurus & Indexes Information Organization and Retrieval

33. Review (cont.) • Check cross references and insert where needed • Produce Test Version • Test by Indexing • Modify as needed • Produce Production Version. Information Organization and Retrieval

34. Testing a Thesaurus • Assign descriptors to a sample set of NEW documents (use enough to get an idea of any gaps in the thesaurus. • Test retrieval using sample questions and seeing how effectively the thesaurus maps to the appropriate descriptor Information Organization and Retrieval

35. The Indexing Process • Concept identification • term selection (via thesaurus) • term assignment Information Organization and Retrieval

36. Does Thesaurus contain term for Concept Can Concept be expressed combining terms? Start Examine Document and Identify Significant Concepts Consider First Concept NO Establish Term Denoting Concept YES YES NO Preferred Term? Select Preferred Term NO Is There Another Concept End NO YES YES YES Consider Preferred Term Consider Each of These Terms Admit New Term Into Thesaurus Assign Terms to Document NO Would Concept be better represented by one of these terms Prefer Alternative Term(s) Consider any associated terms in Thesaurus (NT,BT) YES Application: The Indexing Process (Manual) Select Alternative term to represent Concept NO Is Term suitable Adapted from ISO 5963, p.5 Information Organization and Retrieval

37. Thesaurus Revision and Updates • There will always be new concepts, products, or expressions that need to be added to the thesaurus. • Set a regular schedule of reviews and revisions. • Collect complaints, problems, etc. and fold into revision of the thesaurus Information Organization and Retrieval

38. References • Soegel, D. Indexing Languages and Thesauri: Construction and Maintenance. Los Angeles : Melville Publishing Co., 1974 • Foskett, A.C. The Subject Approach to Information. London: Clive Bingley, 1982. • Standards: • ANSI/NISO z39.19--1994 -- American National Standard Guidelines for the Construction, Format and Management of Monolingual Thesauri • ANSI/NISO Draft Standard Z39.4-199x -- American National Standard Guidelines for Indexes in Information Retrieval • ISO 2788 -- Documentation -- Guidelines for the establishment and development of monolingual thesauri • ISO 5964-- Documentation -- Guidelines for the establishment and development of multilingual thesauri Information Organization and Retrieval