A_quick_guide_to_web..

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A QUICK GUIDE TO:
• EFFECTIVE WEB
SEARCHING.
• SUCCESSFUL SITE
EVALUATION.
EFFECTIVE WEB
STRATEGIES: KEY WORDS.
• WWW.
• WEB
BROWSER.
• SEARCH
ENGINE.
• SUBJECT
DIRECTORY.
• URL.
• BOOLEAN
OPERATORS.
WHAT IS THE WWW?
• Millions of pages of information.
• Includes text, graphics, photographs,
sound and video.
• Hypertexts: texts with links to pages at
other sites elsewhere on the Web.
• Web browsers give access to it.
WHAT IS A WEB BROWSER?
• A Web browser is a computer program
that allows you to view pages on the
World Wide Web.
The two most common browsers are:
• Netscape.
• Internet Explorer
NETSCAPE
INTERNET EXPLORER
HOW DO YOU GET ACCESS TO
WEB PAGES?
YOUR BROWSER
CONNECTS TO
THE SERVER AND
REQUESTS A PAGE
SERVER MACHINE
RUNNING A WEB
SERVER
THE SERVER SENDS
BACK THE REQUESTED
PAGE
YOUR MACHINE
RUNNING A WEB BROWSER
WHAT ARE SEARCH
ENGINES?
SPECIAL WEB
PAGES THAT
HELP YOU FIND
MATERIAL .
HOW?
Just type a search
word or phrase into the
search box and the
search engine will:
• Search its own
database.
• Return results
presented in order of
relevance
HOW DOES A SEARCH
ENGINE WORK?
• It uses robots or “spiders” to search the web
and build its database.
• The database consists of indexed
documents.
• Your query is checked against the search
engine keyword index.
• The best matches are displayed on screen as
hits.
How does
a search
engine
work?
LOCATES
Finds new
pages or
changed
information
on a page
CRAWLS
Internet
Every word
on the page
or some
words on the
page
VISITS
Spider
or Robot
LAUNCHES
RETURNS
Search Engine’s
Server
PRODUCES
Search
engine’s
database
index
(Page created by Kathleen Schrock)
SEARCHES
RECEIVES
User
SEARCH ENGINES: YAHOO
Try it out at: Http://www.yahoo.com
WHAT ARE SUBJECT
DIRECTORIES?
• SPECIAL WEB
PAGES WHERE
INFORMATION IS
CATEGORIZED BY
SUBJECT.
HOW?
• Each main topic has a
list of subtopics.
• Humans, not robots, are
responsible for
cataloguing directories
material.
• Best used when
searching for broad
topics .
Main topic
Subtopics
How does a
directory
work?
VISITS
EVALUATES
Internet
Directory
Employee
ADDS and “CATALOGS”
PRODUCES
Directory’s
Server
Directory’s
searchable
index
Directory’s
browsable
categories
RECEIVES
SEARCHES
(Page created by Kathleen Schrock)
User
BROWSES
WHAT IS A URL?
URL: Uniform Resource Locator:
• The address of any resource on the
Internet that is part of the WWW.
Ex 1: http://www.itisvinci.com
Ex 2: http://www.itisvinci.com/~calanca
Ex 3: http://www.itisvinci.com/users/
calanca/ public_html
HOW TO INTERPRET A URL
The tilde sign (~) indicates personal
directories of individuals
http://www.itisvinci.com/~calanca
Top level Domain.
It specifies what type
Hyper Text
of site it is.
Transfer Protocol
The site has a directory
(A WWW page)
called Calanca.
Server name
(the name of the machine,
where the information is located)
WHAT DOES IT MEAN IF A
URL ENDS IN THE
FOLLOWING?
•
•
•
•
•
•
•
•
.com
.net
.mil
.gov
.edu
.ac
.org
.it .uk .us .ca
•
•
•
•
•
•
•
•
company
network
military
government
educational
academic
non-profit organization
country codes
Search engine results often take you deep within
web sites. Do you want to know where you are?
http://www.itisvinci.com/users/
calanca/ public_html
Home page
Directories
DELETE DIRECTORY NAMES
AND PRESS THE RETURN KEY.
WHAT ARE BOOLEAN
OPERATORS?
Special logical tools that allow you to:
• Broaden your search.
• Narrow your search.
The most commonly used are:
AND, OR ,NOT
Not all search engine allow their
use to refine your search.
DO YOU WANT TO NARROW
YOUR SEARCH?
Boolean
Education
AND
AND
Policy
You want both terms to appear in the documents.
This way you exclude irrelevant hits.
DO YOU WANT TO BROADEN
YOUR SEARCH?
Boolean
Education Policy, GB
OR
OR
UK
You want at least one of the terms to appear in the
documents.
DO YOU WANT TO EXCLUDE
A TERM?
Boolean NOT
Nirvana AND
Buddhism
NOT
Cobain
This way you can exclude irrelevant hits.
Good queries = good results
Poor queries = poor results
Allow yourself enough time to formulate your
query.The more precise your query, the fewer
documents to review.
HOW CAN YOU IMPROVE
YOUR QUERY?
• Use nouns as keywords.
• Use wildcards *.
• Don’t include articles,
pronouns conjunctions or
prepositions.
• Be aware of
capitalization.
• Use enough keywords (up
to 7 or 8 of them)
• Make a list of synonyms.
• Use phrases within
quotes.
• Be aware of spaces
within words.
• Use nouns as keywords,
avoid modifiers (adj.,
adv. etc..)
Nouns are precise terms that
correspond to concrete objects,
while modifiers can easily be
substituted in descriptions.
• Don’t include articles,
pronouns conjunctions or
prepositions.
They are NOT considered
by search engines.
• Use enough keywords
(up to 7 or 8 of them).
• Make a list of synonyms.
Key in enough words to
describe exactly what you’re
searching.
Use synonyms to refine
your search.
• Use wildcards *.
• If you want to broaden
your search, then use
wildcards.
The asterisk * allows you to
search for several words
with the same root at a
time. EX:
ASSIST*
ASSISTANT
ASSISTANTS
ASSISTANCE
Use lower cases, unless you
are searching for proper names. Ex:
If you search for the word
search
heart
you’ll find documents containing :
heart, Heart, HEART.
• Be aware of
capitalization.
BUT
If you search for
Heart
search
you’ll only come out with documents
containing the word “Heart” in capital
letter.
Write phrases within quotes every time
you search for documents containing
all the words in your query in the exact
order you wrote them.
Ex:
• Use phrases within
quotes.
“Successful Web Search Strategies”
search
you’ll find documents containing the
words you typed into your search box.
Watch out for spaces between
words.
In the case of:
“Successful Web Search Strategies”
search
• Be aware of spaces
within words.
the use of additional spaces between
words would cause the search for the
right document to fail.
DO YOU WANT TO KNOW
MORE?
TRY OUT FOLLOWING LINKS:
http://completeplanet.com/Tutorials/Search/index.asp
http://school.discovery.com/schrockguide/ppoint.htm
END OF PART 1
PART TWO
SUCCESSFUL SITE
EVALUATION
SUCCESSFUL WEB SITE
EVALUATION
Have you ever
considered that:
• Not all of the information on the
World Wide Web is accurate
• Not all websites are good.
HOW CAN WE FIND GOOD
WEBSITES?
THE FIVE DEAR OLD
QUESTIONS
• WHO is the author?
(is he an expert, can
we recognize him/her
as such?)
• WHERE does the site
information come
from? (primary or
secondary info?)
• HOW is the
information given?
(objective, biased, fact
or opinion?)
• WHEN was the site
created? Is it updated?
• WHY was it created?
Is the aim clear?
LIST OF QUALITY CRITERIA
FOR WEB INFORMATION
•
•
•
•
•
•
•
AIM
ACCURACY
AUTHORITY
CURRENCY
DEPTH
DESIGN
REGULARITUY OF UPDATE
AIM
• Are the aims of the site/page clearly stated?
• Does the site/page achieve its aims?
• Are there any hidden aims (product
promotion, indoctrination)?
ACCURACY
LANGUAGE ACCURACY
• Are there any spelling mistakes?
• Are there any grammar mistakes?
CONTENT ACCURACY
• Has the content been reviewed by a third
party?
• Are there any references and
bibliographies?
• Check the URL
Does the URL contain the following?
.edu
.org
.ac
.gov
The information is more likely
to be correct.
• Can you contact the author?
Is there an e-mail address/
contact address/phone number?
If you have any
doubts
contact him.
AUTHORITY
• Who is the author?
• Is he/she an expert?
• What institution has published the material
on the Web?
• Check the URL domain
Imagine you used a search engine to find
information about “videoconferencing”.
You decide to try out this address.
http://www.icbl.hw.ac.uk/ltdi/ltdi-pub.htm#VCStudies
Learning Technology
University
Dissemination Initiative
(What Institution?)
(A Project by Heriot-Watt
Heriot-Watt
University)
University
(Where?)
In the United Kingdom
CURRENCY
•
•
•
•
When was the page/site created?
Is this stated or not?
Is the material regularly updated?
Are there any dead links on the page/site?
Beware of outdated material!!
DEPTH
• Does the site provide exhaustive coverage
of the topic you searched for?
• Does it claim to be comprehensive and turns
out to be very poor, instead?
DESIGN part 1
• The speed of download
• The ease of navigation
• Does the page/site download
quite fast?
• Are there too many
images/frames that cause
download to be too slow?
• Is the resource organized in
order to be browsed easily?
• Are there buttons helping
navigation? (i.e. back,
forward, home).
• Is there a site map?
REGULARITY OF UPDATE
•
•
•
•
Is the site updated at regular intervals?
Can you see that it is?
Are the links regularly updated?
How many dead links are on the page/site?
DESIGN part 2
• The colour scheme
• Compatibility
• Have colours been well used?
• Is the page /site easy to read?
(yellow characters on a red
background are probably
better to be avoided)
• Does the page/site require
specific software to be
accessed?
• Is the resource material
recognized by all browsers?
DO YOU WANT TO KNOW
MORE?
Try out this address:
http://www.sosig.ac.uk/desire/internet-detective.html
An interesting, interactive tutorial to become
an Internet
Detective
BIBLIOGRAPHY 1
• Web Searching
Tutorial: Guide to Effective Searching of the Internet:
http://completeplanet.com/Tutorials/Search/index.asp
• ICT4LT Module 1.5 Introduction to the Internet:
http://www.ICT4LT.org
• "Successful Web Searching Strategies”:
http://school.discovery.com/schrockguide/ppoint.html
• "A helpful Guide to Web Search Engines”:
http://www.monash.com/spidap4.html
•
BIBLIOGRAPHY 2
• "Search Engine Math”:
http://searchenginewatch.com/facts/math.html
• "Exploiting Internet resources Off-Line" (Graham Davies):
http://ourworld.compuserve.com/homepages/GrahamDavies1/
gdghent.htm
• "Web Skills for Language Learning" (Charlie Mansfield & Tom
McNeill):
http://www.well.ac.uk/wellproj/wellbook.htm
Bibliography 3
Web Sites Evaluation
•
"Evaluating Websites”
http://servercc.oakton.edu/~wittman/find/eval.htm
•
"The ABCs of Web Site Evaluation”
http://school.discovery.com/schrockguide/ppoint.html
•
"Where are the good Web Pages?" (David Eastment)
http://www.eastment.com/eval.html
•
"ICT4LT Project:Evaluation Form"
http://www.ICT4LT.org
•
How to search the web:" Internet Detective"
http://www.sosig.ac.uk/desire/internet-detective.html
THE END
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