Introduction to Information Literacy 1 M03: Access of Information Identify Search Evaluate Use...

Introduction to Information Literacy 1

M03:Access of Information

Identify

Search

Evaluate

Use

Present

See also:

Chapter 3 and Chapter 5, Riedling.


Outline

SearchingResourcesTools (for searching the Internet)

Search engines Subject directories / web directories Invisible web / deep web

StrategiesTechniques


Review: The Steps in an Information Research Process

Identify

Search

Evaluate

Use

Present

Identify To identify the problem and the information needs.

Search To develop a search strategy and to search the

information you need. Evaluate

To evaluate the information obtained. Use

To extract, summarize and analyze the information to solve the problem.

Present Write a paper and give a presentation. Do not

forget to cite the information sources.


How do I Get the Information I Need?

Searching

Resources: Where to search for information?

Tools: What tools can I use to search the Internet?

Strategies: Think before you search!

Techniques: How to get better search results?


Resources:Where to search for information? Printed materials

books, journals, magazines, newspapers, library catalogs, etc.

Non-printed materials and the InternetVideos, audios, verbal (talking to people),

periodical databases (including online databases), and the Internet

Note: Some materials are available in both printed and electronic format.

Our focus


Tools:Searching the Internet The Internet contains a lot of information,

but it is not indexed like the library’s catalog.

Searching the Internet requires part skill, part luck, and a little bit of art.


The Various Search Tools on the Internet Search engines

Uses a computer program (called web-spider) to navigate through the web and collect information about web pages.

Subject directories / web directories Manual entry and classification

Invisible web / deep web Includes dynamic electronic databases that are not

searchable through search engines.


Tool #1: Search Engines

They maintain a large index for a huge number of Internet sites by retrieving each individual web pages. Google claims to have indexed

8,058,044,651 web pages, as of 22nd June 2005.

Examples: Google: http://www.google.com AltaVista: http://www.altavista.com Yahoo!: http://www.yahoo.com

Note: Sometimes it is better to use a special-purpose search engine. E.g. Would you use Google to query about a KMB bus route?


Can search engines find everything on the Internet? No. Search engines cannot index the

pages in the invisible web / deep web: Pages which are not linked to by other

pages. Dynamic Web pages based on

responses to database queries. Sites that require registration or

otherwise limit access to their pages.

More on dynamic web pages later in this module.


Page Ranking Policies Important question: How do search engines

rank their search results? Relevancy to the search keywords Importance of the pages (e.g. More links to the page

from important sites indicates importance.)

Some search engines put advertisers' pages at the top, called paid placement, sponsored links or sponsored listing.


Special Topic:Meta-Search Engines They search other search engines,

then combine and organize the results from those searches. Thus, they do not maintain indexes of web pages.

Examples: Profusion: http://www.profusion.com Metacrawler: http://www.metacrawler.com Info.com: http://www.info.com


Meta-Search Engines:A Potential Problem Usually too much information is found

instead of not enough. The usefulness of meta-search depends

on how good the combining and organizing functions are.E.g. How well does the meta-search engine

eliminate duplicated results?


Special Topic: Newsgroups

Newsgroups are discussion forums available through Internet services providers, as well as at Lingnan University.

Each group is usually dedicated to a certain discussion topic. The topic is usually reflected by a unique name. e.g. talk.politics.european-union lingnan.hostelc

Access through a news reader software. E.g. Mozilla / Netscape / Thunderbird Microsoft Outlook


Searching the Newsgroups The newsgroups contain the following kinds of

information that may be difficult to find elsewhere: Personal opinion and other informal information Very specific but unpopular topics (e.g. the solution to a rare bug

in Microsoft Word, which may not have been formally documented)

Very current topics about which web sites are not yet available

Use Google Groups to search through various newsgroups: http://groups.google.com When reading a post in a newsgroup, please pay special

attention to the date of a post and the group in which the post belongs. These help you evaluate the usefulness of the post. (We will learn more about information evaluation in M05.)


Problems Related to Newsgroups Virtually any one can view and

post in a newsgroup. This leads to the following problems: Many spam (junk) posts (e.g.

advertisements) Privacy: others may capture email

addresses from the posts Many uninformative or inaccurate

posts


Tool #2: Subject Directories

Also called web directories A directory on the World Wide Web that specializes in

linking to other web sites and categorizing those links All linked pages are classified and reviewed by human Examples

Yahoo: http://www.yahoo.com Google: http://directory.google.com Open Directory Project: http://www.dmoz.org


Subject Directories vs. Search Engines Many people do not make enough use of

the subject directories. Instead, they go directly to search engines.

Keep in mind that subject directories often contain carefully chosen lists of quality Internet sites. They are sometimes more useful than a search engine.


Tool #3: Invisible Web / Deep Web

There is a huge amount of information that is stored in databases accessible on the Web, but not available via search engines.

It is likely to contain very current, dynamically changing information, including news, job listings, airline flights, etc.

E.g. Online electronic databases at the Lingnan University library


Strategies:Think before you search!

The general strategies of a search:

1. Pre-search analysis

2. Executing the search

3. Looking for an overview

4. Seeking expert advice


Pre-search Analysis Identify any societies, organizations that have the

information you sought at their websites E.g. To get a list of Government Departments in Hong Kong, it is

faster use visit the Hong Kong Government’s official website, instead of using a search engine.

Identify any distinctive words, phrases, acronyms associated with the topic.

Identify other words that are likely to appear in any web pages over the topic.

Identify any synonyms, variations in spelling for the previously identified words or phrases, e.g. using OR.


Pre-search Analysis (Cont’d)

Identify any irrelevant documents that these search words/phrases may pick up.

Identify other words/phrases to describe the broader subject area that may be useful when searching a subject directory

Prepare the search terms according to the techniques discussed in Boolean Search


Executing the Search

Use your search terms in a search engine Use Boolean operators to increase or

decrease the number of matches, as described previously.


Looking for an Overview

Search in a subject directory using the broader subject term

Search in a subject directory using your narrower keywordsLinks from the subject category should point

you to the main sites about the subject Lookup the subject matter in an

encyclopedia (e.g. Wikipedia)


Seek Expert Advice

Seek advice from relevant mailing lists, newsgroups, or other discussion groups.

Sometimes you come across experts in those forums who can point you to difficult to find articles or resources.

Search Google Groups if you think the topic may have been previously discussed in newsgroups.


Techniques:How to get better search results? Phrase search Boolean operators

AND, OR, NOT Stop words Wildcards


Phrase Search Example:

You want to find information about a person called Lee Sai Man.

lee sai man

“lee sai man”

LAW Pui Man. A. LEE Kam Fung. A. LEE Sai Po.

Google gives:With double quotation marks:

Lee Sai Man, Ng Sze Kun, Julia, 000009452XXX,…

Google gives the result above, plus the following:

However, without the double quotation marks:

(This is called Phrase search.)


Boolean Search

Salt AND sugar

salt sugar

Salt OR sugar

salt sugar

Salt AND NOT sugar

salt sugar

Each search engine may use different syntax and rules for OR, NOT, AND. You should check up the help pages for your favorite search engines.In many search engines, AND is implicit by default.


Boolean Search Examples

OR search example: museum (london OR paris)

NOT search example: "comparative literature" NOT "department of"

Google uses - to indicate NOT in Google: "comparative literature" –"department of"

Reference: Google Help Center


To Get Fewer Matches…

Using more AND terms can also narrow the search or reduce the number of matches, e.g.:"president bush" AND "iraq war" AND WMD AND claims


To Get Fewer Matches…

Using NOT can further eliminate groups of matches, e.g.:"comparative literature" NOT "department of"

sars NOT "south african revenue service" NOT "south africa"


To Get More Matches…

Using more OR terms will increase the number of matches, e.g.:- profitability airline gives 265,000 matches

in Google, while profitability airline OR airlines gives 685,000 matches.

Use a broader term: E.g. Use operating system instead of windows


Stop Words and Wildcards

Search engines stop words:common words such as the, in, 3, etc.are ignored by most search engines as

search keywords Some search engines support wildcards: book* will match books, bookstore, bookworms, etc.

Introduction to Information Literacy 1 M03: Access of Information Identify Search Evaluate Use...

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