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13 CLASSIFICATION AS A SEARCH TOOL Do you have anything on ‘stegosaurus’? stegosaurus dinosaurs prehistoric animals, prehistoric life  you’re making use of classification! Alternative approaches!

USE THE AUTHORITY LISTS AND THESAURI most people would know ‘stegosaurus is a dinosaur’ one may not always be aware of the context as alternative approaches  Alphabetical lists of subject headings or thesauri are useful (for indexing and searching) i.e. RCN Library Thesaurus of Nursing Terms, FERTILISATION UF Human fertilisation BT Reproduction NT Assisted conception RT Fertility Used for indexing and searching must be indexed under the term ‘fertilisation’  controlled

IN NATURAL LANGUAGE… (1) An enquirer is searching a natural language system for information on the possible use of parachutes to slow down ocean-going ships. A search is made under ‘Parachutes AND ships’  Nothing is found! a relevant documet in the information system entitled ‘Putting a halt to super tankers’  Does not include the word ‘ship’

IN NATURAL LANGUAGE… (2) indicates that among the possible alternative terms to ‘Ships’ is the narrower term ‘Tankers.’ amends the search to ‘Parachutes AND Tankers’ without this, the search a) have assumed that there is nothing relevant in the system, or b) have used some other source or possible alternative search terms Tankers NT Ships

BOOLEAN SEARCHING ‘Parachutes AND ships’ (operator) – Boolean operators : AND, OR, NOT  ‘Venice AND Climate’  ‘Venice AND (Climate OR Weather)’  ‘Venice AND (Glass NOT Crystal)’

FULL TEXT DATABASE (1) full text search: search a complete text for a single word or term  a knowledge of classification is no longer necessary for the information worker?  (But) Boolean search involves elements of classification search for the subject of this book: ‘Classification’ 1) 1st step: get results  stoo many search results!  many irrelevant results (a number of different subject areas: ‘Biology’, ‘Diseases’, ‘Plants’; and so on)

FULL TEXT DATABASE (2) search for the subject of this book: ‘Classification’ 2) 2nd step: narrow the search  add second term, such as ‘information retrieval’ (Classification AND Information retrieval)  reduce the number of items retrived and increase their relevance Classification Information Retrieval

FULL TEXT DATABASE (3) Imagine that a user searches for the term ‘Churches’ and gets the response  Your search did not match any documents: Try to broaden your search using more general keywords Enter more general, broader term ‘Buildings’ or ‘Architecture’  requires some more explicit form of hierarchical calssificatory facility  The use of classification is essential for efficient subject access Churches Building Architecture

USE OF THE CLASSIFICATION SCHEDULE notation can help solve terminological problems and allow complex subjects to be represented by simpler coding DDC  ‘Birds’, ‘Ornithology’, ‘Aves’ DDC  ‘Mechanisation and automation of factory operations’ British Catalogue of Music Classification QPG  ‘Suites for solo piano’

SEARCH FOR THE CLASS NUMBER (1) Enumerative classification - DDC LCC TL783.5 Faceted classification - Thesaurofacet RKM/SBH Spacecraft : Nuclear propulsion or or RKM/SBH (pre-) Spacecraft or Nuclear propulsion or RKM or SBH (post-) ‘Nuclear propulsion systems for spacecraft’ ‘Spacecraft’ / ‘Nuclear propulsion’

SEARCH FOR THE CLASS NUMBER (2) post-coordinate indexing  coordinated by the searcher  Boolean searching : ‘Space AND Nuclear propulsion’  faceted classification : RKM AND SBH Hierarchical enumerative system  pre-coordinate only Faceted scheme  pre- or post-coordinate

SEARCH FOR THE CLASS NUMBER (3) Searches can be broadened or narrowed by reducing or increasing the number of elements i.e. London Classification of Business Studies, ‘Safety measures for materials handling in the explosives industry’  CMG AND JZRD AND KDQ (materials handling) (Safety measures) (explosives industry)

SEARCH FOR THE CLASS NUMBER (4) broaden the search by reducing the number of elements CMG AND JZRD AND KDQ : ‘Safety measures for materials handling in the explosives industry’ CMG AND JZRD : ‘Safety measures for materials handling’ CMG AND KDQ : ‘materials handling in the explosives industry’ JZRD AND KDQ : ‘Safety measures in the explosives industry’ KDQ : explosives industry’  Faceted scheme

SEARCH FOR THE CLASS NUMBER (5) broaden the search by ‘truncation’ device ‘comput*’  computer, compters, computing, computerization, computerisation DDC ‘Churches’ ‘Churches’ (Buildings associated with Christanity) ‘Religious building’ - 72 ‘Architecture’  Hierarchical scheme

CHAIN PROCEDURE (1) chain – classification hierarchy for a subject - alphabetical entries derived from the classification number - UDC ‘Public health aspects of pertroleum pollution of sea water’ (26): Technology 61 Medicine 614 Public health Pollution Water pollution (26) Seas (26): Oil. Petroleum Petroleum: Sea water pollution: Public health (26): Oil: Sea water pollution: Public health (26): Sea water pollution: Public health (26) water pollution: Public health pollution: Public health Public health 614 Medicine61 Technology6

CHAIN PROCEDURE (2) Relative index Petroleum: Economic geology Petroleum: Mining Petroleum: Sea water pollution: Public health (26):665.6 example : British National Bibliography (BNB) - Works are arranged by the DDC and name, title, and subject indexes - Chain procedure was used to produce the printed subject index between 1950 and 1970

PRECIS AND COMPASS (1) PRECIS(PREserved Context Index System) BL decide to produce the BNB by computerized method, chain was replaced by PRECIS in PRECIS was independent of any particular classification scheme Aircraft Engines. Design  Similar entries would be made under ‘Engines’ and ‘Design’  system provide automatic production of reference to link synonymous or related terms.

PRECIS AND COMPASS (2) COMPASS was developed and introduced to replace PRECIS in 1990  Simplified PRECIS (PRECIS is for a printed output)  retained the essential appearance of PRECIS entries  In 1996, COMPASS also terminated and BL applied LCSH. (broad subject heading approach)

USING A THESAURUS AS AN AID TO SEARCHING ONLINE CATALOGUES African Studies Thesaurus  used for indexing and retrieving material in the library collection and  directly linked to the catalogues i.e. ‘dairy industry’ dairy industry Search catalogue Used for dairy products industry Broader terms food industry Narrower terms cheese industry Related terms dairy farms milk Search catalogue Broader terms beverage Related terms dairy industry

USING THE COMPLETE CLASSIFICATION SCHEME FOR SEARCHING Class number Dewey subject Nautical engineering and seamanship – Navigation – Selection and determination of course Dewey index Navigation – Technology – Seamanship Navigation – aquatic sports Navigation – maritime transportation Navigation – maritime transportation – law Navigation – space flight Navigation aids Navigators

CONCLUSION Classification (Sevenonius) : - improve recall and precision, save the time of the user - provide a structure for meaningful browsing (hierarchies) - serving as a mediating or switching * language * Switching role. i.e. Broad System Ordering, BSI Root Thesaurus

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