INFS 321 Information Sources

Transcription

1 INFS 321 Information Sources Session 11 Electronic Resources I Lecturer: Prof. Perpetua S. Dadzie, DIS Contact Information: pdadzie@ug.edu.gh College of Education School of Continuing and Distance Education 2014/ /2017 godsonug.wordpress.com/blog

2 Session Overview At the end of the session, the student will be able to : Understand the history of e-resources State uses, advantages & disadvantages of CD-ROM Explain what a database is, state different types and uses of databases Know the databases that the University of Ghana subscribes to Describe process of searching databases Prof. P.S.Dadzie, DIS Slide 2

3 Session Outline The key topics to be covered in the session are as follows: Topic One : History of E-Resources Topic Two: CD ROM and its usage Topic Three: Online Databases and its usage Topic Four: University of Ghana Databases Topic Five: Search strategies for E-Resources Prof. P.S.Dadzie, DIS Slide 3

4 Reading List Katz, A. William (2002) Introduction to Reference Work Vols. I Chapter 1 Prof. P.S.Dadzie, DIS Slide 4

5 Topic One HISTORY OF E-RESOURCES Prof. P.S.Dadzie, DIS Slide 5

6 History of E-Resources E-Resources began with development of computerassisted typesetting and printing Before computer technology advancements in late ϭϵϲϭ s, liďrariaŷs ĐoŶsulted staŷdard priŷted refereŷđe work publishers of indexing and abstracting services first used computers to print paper products created magnetic tapes- librarians searched for indexed term for bibliographic citations to articles

7 History of E-Resources 2 Magnetic tape and punch cards query keyed daytime, magnetic tape run against query at night; results delivered next day Any typographical or logical errors in query required re-doing search and waiting for new results. queries processed so slowly, done in batch mode; Process - batch processing, formed foundation of information retrieval industry in 1960s.

8 History of E-Resources 3 DuriŶg ϭϵϳϭ s Đoŵputer power, speed aŷd ŵeŵory all increased Communication with computers over existing telephone wires also increased. Magnetic tape replaced by much faster disk stacks Modems allowed remote access to huge computers rather Information service companies made computerized files, (called Databases) available to other libraries on a contractual basis. The database or reference work in machine-readable form searched online and information needed is received directly

9 History of E-Resources 4 This is known as online searching. These developments provided first truly online searching, with searcher and search systems communicating interactively number and variety of databases increased, market expanded included most colleges, universities, corporations, research libraries and institutions primary user for all abstracting and indexing services was professional reference librarian in these organizations.

10 History of E-Resources 5 Librarians performed searches on behalf of library user called retrospective searches, bibliographic searches, online searches or mediated searches. Over time, demand for direct access to electronic resources began; vendors created new services menu- based to facilitate searching. information industry developed first end-user systems. These initial end-user search services were transitional stage of development for electronic resources.

11 Topic Two CD ROM Prof. P.S.Dadzie, DIS Slide 11

12 CD-ROM Available since mid-ϭϵθϭ s shiŷy ĐoŵpaĐt disđ Đalled CD-ROM Vast storage capacity provides user ability to search index, abstract or other reference tool directly Users able to explore database, printing out citations during search For reference librarian CD-ROM systems have single fixed subscription price for unlimited use

13 CD-ROM 2 Advantages Simplifies budgeting, since annual costs known in advance and do not vary with use designed to be end user system, reference librarian does not have to be search intermediary Disadvantages tend to be expensive lack of standards, High Sierra Standard resulted in a degree of incompatibility among CD-ROM systems systems with different search levels impede searches or need individualized training and instruction CD-ROM and online version of same database vary significantly from one another and from printed version

14 CD-ROM 3 Online database tends to be updated frequently while CD-ROM updated quarterly, semiannual, or annual basis investigate and cross check information from a variety of sources

15 Topic Three DATABASES Prof. P.S.Dadzie, DIS Slide 15

16 Databases collection of information on one or more related topics a set of information formatted into defined structures store unlimited amount of information and make them readily available in a matter of seconds Accessed over communication network

17 Types of Databases Bibliographic and Non bibliographic Bibliographic - machine-readable form of indexes and abstracts base record is a citation to an article, book, chapter or paper citation may include abstract or summary of the item, subject headings selected by the database producer, author, title and source information

18 Types of Databases 2 Non Bibliographic- variety of databases distinguished from bibliographic databases by content, style or format contain information other than citations to books, journal articles or other publications two broad groups: textual databases & numeric databases textual databases - contain information equivalent to commonly encountered printed reference sources such as encyclopedias, directories and other publications

19 Types of Databases 3 Textual databases Full-text databases base record is full paper or document or article itself, with associated bibliographic citation information Numeric databases : databases containing historical and predicative information the EIU COUNTRY RISKS AND FORECASTS database produced by Economist Intelligence Unit

20 Types of Databases 4 Bibliographical Utility Networks OCLC (Online Computer Library Center) begun in 1967 In 2000, bibliographic records and holdings information for more than 36,000 libraries in 74 countries 43 million records for books, serials, audiovisual materials, maps, archives/manuscripts sound recordings, music scores and computer files Access to OCLC Online Union Catalog (WorldCat)

21 Types of Databases 5 The Research Libraries Information Network (RLIN) shared cataloguing network operated by the Research Libraries Group (RLG) in 2000, 161 institutions, including university libraries, archives, museums and other research or educational bodies union catalog of more than 105 million items held in RLG member institutions, plus an additional 100 libraries that use RLIN.

22 Topic Four UNIVERSITY OF GHANA ONLINE DATABASES Prof. P.S.Dadzie, DIS Slide 22

23 Databases subscribed by UG Agora American Institute of Physics American Physical Society Annual Reviews BioOne Cambridge Journals Chicago Journals Cochrane Medical Library EBSCOhost Emerald Faculty of 1000 Medicine Geological Society HINARI Institute of Electronic and Electrical Engineers 23

24 Databases subscribed by UG Institute of Physics JSTOR Mary Ann Liebert Inc Mendley Nature Publishing Optical Society of America Oxford English Dictionary Oxford Journals Royal College of Physicians Royal Society Royal Society Journals online Royal Society of Chemistry : RSC journals archives Sage Journals Online ScienceDirect Scopus Wiley - Blackwell (formerly Blackwell Publishing) 24

25 Free resources on the Internet African Journals Online (AJOL) BioMed Central Database of African Theses and Dissertations (DATAD) Directory of Open Access Journals (DOAJ) ( Directory of Open Access Repositories (OpenDOAR) Google Scholar Highwire Press Popline1 25

26 Topic Five SEARCH STRATEGIES Prof. P.S.Dadzie, DIS Slide 26

27 Search Strategies To obtain information from a database or a CD- ROM, the user must know a series of commands that allow one to find needed information Subject terms and or key words, author names titles are some of primary keys of retrieving information search or research query which requires a good deal of skill on the part of the user key to subtle searching is Boolean Logic.

28 Boolean logic logic uses common words as logical operators; AND, OR and NOT allows one to combine words and phrases to either limit or expand the search operator OR - to make a more inclusive set by making an item eligible if it meets at least one of the stated criteria item would be included in a set if it meets condition A or condition B.

29 Boolean logic 2 operator OR - to make a more inclusive set by making an item eligible if it meets at least one of the stated criteria item would be included in a set if it meets condition A or condition B. college OR university

30 Boolean logic 3 operator AND - to make a more restrictive set by requiring that an item must meet both the conditions stated to be included in the final set an item would be included only if it meets both condition A and condition B. poverty AND crime

31 Boolean logic 4 operator NOT is also used to make a more restrictive set excludes items meeting condition A that also meet condition B. cats Not Dogs

32 Boolean logic 5 Implied Boolean refers to a search in which symbols are used to represent Boolean logical operators (+) represents AND the minus sign (-) represents NOT no sign at all as an OR relation. Examples: +school_of_public_health +harvard_university +titanic -movie

33 Boolean logic 6 Phrases or combinations of words "harvard university library" OR harvard_university_library Predetermined language in a user fill-in template all of these words (=AND) any of these words (=OR) must not contain (=NOT)

34 Boolean logic 7 Truncation shortening a word or eliminating some characters from a longer term to pick up variants a form of the Boolean operator OR. items that share a common sequence of characters, even if they do not share all the same characters are put into single set prođess Đalled wildđard searđh or steŵŵiŷg

35 Boolean logic 8 Symbols used in truncation asterisk (*) question mark (?) colon (:) plus sign (+) Types of truncation Left - *ship librarianship, statesmanship, Right libr* - library, librarian, libraries, Middle- labo@r - laďor or labour or laďorer or labourer

36 Video Boolean Searching Basics <iframe width="560" height="315" src=" g" frameborder="0" allowfullscreen></iframe>

37 Activity Practice Questions What are the advantages of electronic reference sources over print reference sources? Enumerate at least five databases in CD-ROM What are the challenges associated with the use of CD-ROMS

38 Reference Katz, A. William (2002) Introduction to Reference Work Vols. I Ch. 1 & 2