1 / 206

Internet en WWW voor het opsporen van wetenschappelijke informatie

Internet en WWW voor het opsporen van wetenschappelijke informatie. Paul Nieuwenhuysen Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel pnieuwen@vub.ac.be Meer informatie in digitale vorm via http://www.vub.ac.be/BIBLIO/personal/nieuwenhuysen/courses/opsporen/ IPAVUB.

eyal
Download Presentation

Internet en WWW voor het opsporen van wetenschappelijke informatie

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Internet en WWW voor het opsporen van wetenschappelijke informatie Paul Nieuwenhuysen Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel pnieuwen@vub.ac.be Meer informatie in digitale vorm via http://www.vub.ac.be/BIBLIO/personal/nieuwenhuysen/courses/opsporen/ IPAVUB

  2. Planning van de dag: voormiddag • Over “informatie” • De informatiemarkt • Classificatie- en thesaurus-sytemen • Information retrieval (+ oefenen van query-formulering) • Computernetwerken en Internet i.h.b.; telnet en ftp • World-Wide Web (+ oefenen van “browsing” + “saving”) • Online toegankelijke informatiebronnen! • Globale Internet directories (+ demonstratie van Yahoo!) [Lunch]

  3. Planning van de dag: namiddag (deel 1) • Online toegankelijke informatiebronnen! (vervolg) • Internet indexes (+ oefenen met AltaVista en NL) • Bookshop databases (+ oefenen) • Te betalen databases (+ Gale Directory of Databases) • Gratis databases met titels van tijdschriftartikels (+ oefenen met Ingenta) • Vinden van illustraties (+ oefenen met AltaVista) • Citation searching (+ oefenen met Web of Science) • Documentleverantie

  4. Planning van de dag: namiddag (deel 2) • (Client-server architectuur) • (Evaluatie van zoekresultaten) • [Vrij individueel gebruik van Internet]

  5. About “information” Introductory concepts about information

  6. authority authenticity accuracy objectivity currency / up to date wide coverage format / lay-out of the information reliability distribution medium(print, e-mail, online,...) price / costs stability ... Information sources:evaluation criteria i

  7. The flow of documentary information Author / Sender Primary sources / systems:mainly Journal articles / Books / Electronic mail / Online sources /... Reader/User Secondary sources / systems: mainly Reference works (printed, CD-ROM, online) Library catalogues, including OPACs ...

  8. 8 !? Question !? Task !? Problem !? Why is secondary information created?

  9. Retrospective searching versus current awareness i Past Now Future Retrospective searching Current awareness

  10. Information retrieval: evolution of storage and distribution media i • 1450 print • 1975 + online access databases • 1985 + CD-ROM • 1990 + World-Wide Web (in Internet)

  11. Information retrieval: end user or intermediaries End-userInformation intermediary (Broker or library or ...)Information

  12. About “information” Computer- and network-based information

  13. Information: from bits to meaningful information Digital computer data = bits Information = “documents”, meaningful for and to be interpreted by human beings 01 or Program code, meaningful for and to be interpreted / executed by a suitable / compatible computer

  14. Information: digitally stored and managed information Categories of digital, computer readable information / data, forming electronic “documents”, understandable by human beings. 01 text numbers images video sounds multimedia +

  15. Information: types of digital information 01 • Digital information • Multimedia / Hypermedia Sound Linear text Hypertext Static images Video Programs for computers

  16. Some publication media compared Online / Networked Update speed CD-ROM Printed Volume

  17. The digital / electronic / virtual library Structures & practices of physical libraries and archives Digital /electronic / virtuallibrary Computing Communication capabilities of electronic networking

  18. Scientific publishing in Utopia: an ideal scheme Many authors author = reader in science Many editors / publishers Online remote access multimedia database server Many database search clients and user interfaces one global , international computer data communication network Many readers / users

  19. !? Question !? Task !? Problem !? Indicate the differences between reality and that simplified, ideal schemeof the information flow.

  20. !? Question !? Task !? Problem !? Which basic problems hinder people to find information?

  21. Information retrieval: basic problems (Part 1) i • In many cases it is not completely clear to the user of an information retrieval system which information is in fact needed/required. • In many cases the need for information cannot be expressed completely in the form of a query. One of the reasons is that the complete context of the information need should ideally be expressed, including the knowledge and background of the searcher.

  22. Information retrieval: basic problems (Part 2) i • Language and vocabulary problems • People use different languages and different terms (vocabularies) to describe a similar concept. • The fluidity of concepts and vocabularies: meanings of terms depend on their context and may change over time.

  23. Information retrieval: basic problems (Part 3) i • Too many imperfect retrieval systems • To retrieve and access the information which is in principle available, many different retrieval systems must be available and be mastered. • Furthermore, a perfect information retrieval software does not exist.

  24. Information retrieval: basic problems (Part 4) i • Information overload Users are often overwhelmed by the amount of available information and by the large influx of new information. • The price (or inaccessibility) of particular information A lot of information cannot be obtained or at least not free of charge.

  25. The information industry and the information market

  26. The components of the information industry • Authors • Publishers • Distributors • Users • Related organizations

  27. Online access from an institute to information: methods Online access from an institute to information on • an external online computer host/server systems: • supermarket model: select and pay for selected information only • fixed price per year, payed by the institute to the information distributor • a local server computer, maintained by the institute for their users • for a fixed price per year, payed by the institute to the information distributor

  28. Increase in the number of scientific and technical serial publications

  29. Evolution of information industry: measures • Number of living databases. • Number of database producers. • Number of database vendors (including online services). • Number of database records / documents. • Number of online searches per year. • ...

  30. The information market: growth in the database industry Source: Williams, in: Gale Directory of Databases, 1998.

  31. The information industry / market: future trends (Part 1) • Growth in the production of databases. • Less analogue / hard-copy production = more digital production, storage, and distribution of information. • More integration of information types into multimedia and hypermedia.

  32. The information industry / market: future trends (Part 2) • Growth in the number of • producers and distributors, • end-users searching databases due to easier use and lower costs of information technology

  33. Knowledge organisation: classifications, and thesaurus systems

  34. Examples Classification systems: examples of universal systems • Universal means here: covering all subjects • Examples • Universal Decimal Classification = UDC used mainly outside U.S.A. • Dewey Classification used mainly in U.S.A. • Library of Congress Classification used mainly in U.S.A. • ...

  35. Thesaurus: description • Thesaurus (contents) = • system to control a vocabulary (= words and phrases + their relations) • the contents of this vocabulary • Thesaurus program = program to create, manage, modify and/or search a thesaurus using a computer

  36. Thesaurus relations Term(s) with broader meaning BT (= Broader Term) RT (= Related Term) UF (= Use(d) For) Other term(s) TermSynonym(s) NT (= Narrower Term) Term(s) with narrower meaning

  37. Examples Thesaurus systems covering all subjects: examples • General systems / universal systems / on all subjects = broad and shallow, horizontal systems • Examples: • Library of Congress Subject Headings (LCSH) • thesaurus systems built into word processing software • ...

  38. !? Question !? Task !? Problem !? Try to find more suitable search terms to retrieve “general reviews about monitoring seawater pollution”by using the thesaurus included in the program for word processing that you use. Limit yourself here to the concept of “pollution.”

  39. Databases and computerised information retrieval

  40. What is a database? A database is a collection of similar data records stored in a common file (or collection of files).

  41. Types of databases: examples The databases that form the basis for • catalogues of books or other types of documents • computerised bibliographies • address directories • a full text newspaper, newsletter, magazine, journal+ collections of these • WWW and Internet search engines • intranet search engines • ...

  42. Hints on how to use information sources: overview (Part 1) i • Know the purpose and motivation for each search. • Do not be lazy: search on your own, before bothering experts with requests for advice. • Plan your search in advance. • Choose the best source(s) for each search. • Use the right tools for each job (a suitable communication program for instance, in the case of online searches). • Do not focus on a single source.

  43. Hints on how to use information sources: overview (Part 2) i • Consider citation indexes besides subject-oriented databases, as useful secondary information sources. • Use the available tools for subject searching well. • Try to cope with the language problems. • Match your search strategy with the type of source. • In computer-based retrieval systems, combine search terms when appropriate, using • Boolean operators • proximity operators (for instance “near”,...)

  44. Hints on how to use information sources: overview (Part 3) i • Work cost-effectively. • Use special care when searching for names. • Work iteratively. • Keep a record of your work. • Be critical: not all information is correct or useful. • Stop searching when “enough is enough” • Give up if necessary... (Not all questions have an answer.) • ...

  45. Hints on how to use information sources: subject searching i • When you search for information on a particular topic/subject: investigate if the database producer offers • a subject classification scheme and/or • a controlled/approved/accepted subject terms, and/or • a subject thesaurus • Exploit these, if they are available. • Use synonyms, broader and related terms, if appropriate. • Use narrower terms also, in most cases.

  46. Hints on how to use information sources: Boolean combinations (1) In the case of computer-based information sources, use Boolean combinations of search terms when appropriate and when possible. term x1 OR term x2 OR term x3 term y1 OR term y2 OR term y3 term z1 OR term z2 OR term z3 AND AND AND ...

  47. Hints on how to use information sources: Boolean combinations (2) Most text search systems understand the basic Boolean operators typed in capital characters: AND OR

  48. !? Question !? Task !? Problem !? How many (and which) concepts do you see in a search for “general reviews about monitoring seawater pollution”?

  49. !? Question !? Task !? Problem !? Prepare off-line, on paper, a suitable search query in a generic format, to find “general reviews about monitoring seawater pollution” as the basis for later, concrete searches in databases.(Limit yourself perhaps to 1 concept.)

  50. Hints on how to use information sources: work iteratively Work iteratively = search, investigate your results, refine your search, search again, and so on; do not try to find everything in 1 step, with 1 search. Query Searching Results Feedback

More Related