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Searching for and Accessing Information

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Presentation on theme: "Searching for and Accessing Information"— Presentation transcript:

1 Searching for and Accessing Information

2 Database A database is a collection of data arranged for ease and speed of search and retrieval (The American Heritage Dictionary of English Language, 2000). The quality of being "... arranged for ease and speed of search and retrieval" is what distinguishes a database from a computer network.

3 Database Although databases can be accessed through the Internet, their contents are not retrieved by search engine services (such as Google or Yahoo!). Some databases are available on CD-ROM and networked in some institutions through a subscription

4 Database Every database contains certain types and amounts of information referred to as coverage. 

5 Elements of database coverage
What kinds of documents? (journals, magazines, book chapters, dissertations, audio files, statistical tables, images, web pages, software applications?) Which disciplines? (sociology, chemistry, music, all, none?) What time [periods]? (the current year? ? how often is the database updated? hourly? daily? weekly? monthly? annually?) What languages? (English only? other languages?) Which publication types? (scholarly? popular? trade? all? other?) What is included in the record? (a whole chapter? article? brief description such as bibliographic citation? abstract?) publisher and title?)

6 Other characteristics of a database
A database is any organized collection of data. A database is as an electronic filing system for accessing data. Traditional databases are organized by fields, records, and files. Databases store information in tables; tables store records; each record has fields

7 A field is a single piece of information about an object;
If the object were an Employee, a field would be Firstname, Lastname, or Date of birth.

8 A record is one complete set of fields; In an Employee file, there would be one record for John Smith, another record for Mary Brown, and another record for Sue Black A file is a collection of related records.

9 What is a database Some examples of databases you may encounter in your daily life are: a telephone book T.V. Guide airline reservation system motor vehicle registration records papers in a filing cabinet files on your computer hard drive. 

10 Understanding searches
Databases store data or information in tables, just like the one below:

11 Understanding searches
The table allows you to see all the records stored in the database Tables can store many records

12 A record is all of the data or information about a thing (or a person)
A record is all of the data or information about a thing (or a person). Each bit of information is a field.

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16 Activity Create a record with fields for a driver’s licence.

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19 Field Searching Most searches (e.g. using a search engine, databases) search for “words anywhere” or “keywords” automatically This type of search retrieves more information with less precision This is known as “recall” searching (it focuses on recalling as much information as possible)

20 Fortunately, these retrieval systems allow searching in specific fields (e.g. author, title) and usually refer to this as “advanced” or “expert” searching This kind of searching typically retrieves ...

21 ... less information with more precision (referred to as precision searching)

22 Think about it If you are a detective and the only clues you have for a missing persons case are the words "red," "blue," and "green,“. Who is the missing person? What kind of search?

23 Think about it This is keyword searching

24 Think about it If you knew your person had a red tie, blue shirt, and a green beret, who would be the missing person? What kind of search?

25 Think about it This is field searching What are the fields?

26 QUICK REVIEW

27 There are basic search techniques that are used when searching for information whether using the library resources, databases or the Internet. You would have encountered four pieces of information that are needed when you did the catalogue tutorial.  These are author, title, subject and keyword.

28 Search by author An author search is used to locate works by the author.  The more information about the author you provide, the more limited your search results will be.

29 Title search What is a title search?

30 Title search A title search is used to locate specific titles of books, references, periodicals and other resources.

31 Subject search A subject search is used to find materials on a specific topic

32 Keyword search Keyword search is used when the author or title is unknown.  This is different from the subject search.  A keyword search looks for specific keywords in all fields whereas the subject search is limited to a specific subject heading.

33 Recall vs Precision and Keyword vs Field
When you want to find large amounts of information; general information about a topic, how would you search? When you want to find small number of sources on a specific topic e.g. for course assignments etc, how would you search?

34 NEW INFORMATION

35 Search query Most databases don't understand the natural language we speak and need help understanding what we are looking for. This requires a special set of conventions

36 Conventions Description Quotation marks Around exact phrases (e.g. "university of washington") Logical or Boolean operators Connecting words that narrow or broaden a search to include only what you need. Examples: OR, AND, NOT Wildcards and truncation symbols (* # ? !) For terms that have variant forms of spelling or different possible endings.Examples: child* for child, children, childhood, childish, etc. Nesting Placing terms in parentheses to indicate separate units. (Like an equation, (A or B) not C :

37 Let’s stop here

38 Boolean Operators When searching for information, boolean operators can be used to widen or narrow the search.

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