Transcript Searching Effectively

Preparing To Search
The Internet
Helping Students Search
Effectively
Surfing is not
searching.
“Computers download information—
• They do not teach you to think.
• Computer education imparts technical
skills;
• It does not impart knowledge.”
•
John Rosemond
We already know
how to
use the Web!
Just because you live on
the Web, doesn’t mean
you can’t learn how to
use it more effectively
and more powerfully!
“Not all the information that exists in
the world is on the Internet-Not all the information that is on the
Internet is accurate.”
An hour on the Web may not answer a
question that you could find within two
minutes of picking up a reference book.
Getting Started Searching
• URL’s
• Searching techniques
• Search engines
URL’s
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Uniform Resource Locator
The web “address” that connects you with a website
Goes in the address bar at the top of the screen
Gives you information about the website
Parts of a URL
http://www.starwars.com/seminars.html
• http://--hypertext transfer protocol:
•
the language computers use to “talk” to one another
• www—world wide web:
•
the body of information connected by the cables and computers of the Internet
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.starwars—domain name:
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the structured, alphabetic-based, unique name for a computer on a network
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.com—top
level domain:
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gives an idea of where the document is stored
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/seminars—file
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a folder within a website
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.html—hypertext
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the computer language used to format documents
name:
markup language:
Top Level Domains
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.edu—higher education
.k-12—elementary and secondary schools
.com—commercial
.gov—government agency
.mil—military
.org—general noncommercial organization
.net—computer network
Who Pays For The Internet?
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Advertisers pay for Internet websites.
Popups and banners are trying to influence your spending habits.
The information on commercial sites--.com—may be presented in such
a way as to encourage you to buy a particular product.
Be wary of URL’s with a ~ in the address—this indicates a personal
homepage and does not guarnantee accuracy.
How Do You Find What You Need?
• Libraries and department stores are planned.
• No one is in charge of organizing the Internet.
• Well-prepared searches will eliminate useless hits and
wasted time.
Effective searching
Brainstorming/
Questioning/
Planning
Choosing
the right
type of
search tool
Staying up
to date
Understanding
strategy/
syntax
Evaluating
results!
Four tips: For Sure
• Focus—What is your mission or question?
• Strategize—Which search tools will you use?
Which keywords and search terms will you use
and how will you express them?
• Refine—How might I improve my search results?
• Evaluate—Which results will you visit? Which
sites or documents are worthy enough to use?
Did I do good work?
Good searchers also:
• Use peripheral vision—they mine their results
for additional search terms
• Consult several search tools
• Make use of advanced search screens
• Search the free Web and subscription
databases
• Use appropriate syntax (the language specific
to the search tool they are using)
• Use search strategies
• Modify or refine their searches (Searching is
recursive!)
Before you search, you need to:
• Prepare
• Organize
• Combine
Prepare
• What do you need to know about your topic?
• Make a list of all the terms connected with your topic.
• Include names, organizations, and phrases.
Organize
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Make a list of the words that are critical to your search.
Note terms that you don’t want to see appear.
Discard the rest.
For example…
If you are looking for information about life on the planet Mars, you
don’t want sites popping up about the Roman god of war.
Put that in your list of words you don’t want to see.
What other words might be connected with your topic that will send you to
useless sites?
Combine
Use Boolean operators to combine your most
important terms.
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Use AND to connect the terms you want to see.
Use NOT to exclude terms you don’t want.
Use OR to include similar terms.
Use quotation marks around names or phrases
Use lower case for all proper nouns, except for acronyms
How important AND is!!!
When do you really need OR?
OR is generally used for synonyms o
Use NOT as a refinement
technique when problem words
are likely to come up
eagles NOT Philadelphia
“Martin Luther” NOT King
Recognize the importance of brainstorming
and strategy
Research Question: How effective are drug abuse
prevention programs for young people?
Connect with “ANDs”
Concept 1
Concept 2
Concept 3
Concept 4
or
teen*
“drug
abuse”
prevent*
effectiv*
or
adolesc*
marijuana
program*
success
or
child*
alcohol
treat*
For example…
mars AND planet AND life NOT god
But what if…
you WERE looking for information about the Roman god of war?
The Greeks referred to him as “Ares”, so now your search will look
like this….
mars OR ares AND “god of war”
Notice the quotation marks around the phrase “god of war”
Let’s play Boolean Aerobics!
• Stand up if you have brown hair AND
brown eyes
• Remain standing if you have brown hair
AND brown eyes AND are wearing
glasses
• Remain standing if you have brown hair
AND brown eyes AND are wearing
glasses AND are wearing something
blue
Rockwell Schrock’s Boolean Machine
http://kathyschrock.net/rbs3k/boolean/
“Phrase searching”
• One of your best searching tools!
• Use only for legitimate phrases, names, titles
• “vitamin A”
• “John Quincy Adams”
• Titles “An Officer and a Gentleman”
• Phrase searching is sometimes overused:
Remember: not every group of words is a
phrase
• Sometimes “ANDing” or “NEARing” are better
strategies
What Do You Use To Search?
• Search engines
• Search directories
• Metasearchers
Choosing the right search tool
is an important strategy!
Search engines
Subject directories
Subject Guides
meta-search Engines
specialized directo
Subscription Databases
Search engines
Databases of billions of Web pages, gathered by automated “robots,”
broad, often
overwhelming
searches. Search engines vary in
Aallowing
field guide
to the
search tools
the ways they collect sites and organize results
Metasearch Engines
Search across a variety of search tools and organize the collected
results. Good for a broad sweep type search
Subject directories
Links to resources arranged in subject hierarchies, encouraging users
to both browse through, and often search for, results. Subject
directories are often annotated. They are selected, evaluated, and
maintained by humans.
Specific Subject Guides or Gateways
The work of a subject specialists, subject gateways usually result in
carefully selected and annotated links
Specialized search engines
Search engines that focus their searching in a particular area of
knowledge or interest.
Subscription Databases Pay services often provided by states or libraries
offering premium content in the form of reference materials, journal
and newspaper articles, broadcast transcripts, etc.
Search Engines
• Are like the index in the back of a book
• Let you search for specific words and topics
• Use robots known as spiders to search for
information.
Search Engines:
When to use them
• When you have a narrow topic or several keywords
• When you are looking for a specific site
• When you want to do a comprehensive search and
retrieve a large number of documents on your topic
• When you want to make use of the features in an
advanced search screen or search for particular types
of documents, file types, source locations, languages,
date last modified, etc.
• When you want to take advantage of newer retrieval
technologies, such as concept clustering, ranking by
popularity, link ranking, etc.
Search engines are powerful but they
have limitations!
• They do not crawl the web in “real time”
• If a site is not linked or submitted it may not
be accessible
• Not every page of a site is always searchable
• Few search engines truly search the full text
of Web pages
• Special tools needed for the Invisible/Deep
Web
• Paid placement/sponsored results distract
from real results
When using a search engine
Your goal is to get the best
stuff to appear on the
first two or three pages.
Second Gen Search Tools
Approach relevance in helpful ways:
• Google ranks by link popularity
• Teoma ranks by subject-specific popularity
• Vivisimo offers concept-clustered results
• Surfwax uses human generated indexes—Focus
Words and summaries
• Ixquick Metasearch uses the ranking schemes (top
ten lists) of other search tools
U. Albany Laura Cohen
http://library.albany.edu/internet/second.html
Examples:
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Alta Vista
Excite
Hotbot
Infoseek
Advanced Search Screens
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Google
All the Web
AltaVista
HotBot
Tricks for advanced searchers
seeking a needle in a haystack
• Word stemming:
– wom*n
– lesson* NEAR plan*
• Search within
– Google, AlltheWeb
– Also use “find” to search within a page full of text!
• Field Searching
– Search for keywords in titles, subject tags, file formats
rather than just words anywhere in the text
• Search Engine Features Chart
http://searchenginewatch.com/facts/ataglance.html
Field searching is usually easier in
the Advanced Search area
• title:
• Link check (Google, AltaVista) Helps in
evaluating sites!
– link:mciu.org/~spjvweb
• Media or filetype:pdf or ppt (Google)
Great for finding documents, papers, and
presentations!
• domain:
– domain:jp +edu
Subject Directories-•Are like the table of contents
in front of a book
•Let you search for concepts or subject
categories
• Go from general to specific.
•Sites are added by people.
Subject directories:
When to use them
• When you are just starting out, or have a broad
topic or one major keyword or phrase (example:
“Civil War”)
• When you want to get to the best sites on a topic
quickly
• When you value annotations and assigned subject
headings which may help retrieve more relevant
material
• When you want to avoid viewing the many noise
documents picked up by search engines
Subject directories to count on
INFOMINE: Scholarly Internet Resource Collections
http://infomine.ucr.edu/
A large collection of scholarly Internet resources
About.com http://www.about.com
Offers a surprising number of guide pages, maintained by paid
experts. Not scholarly but very handy for everyday, practical topics
Academic Info: Your Gateway to Quality Educational Resources
http://www.academicinfo.net/
Great for high school and college research
BUBL Link http://bubl.ac.uk/link/
This UK project leads to carefully selected and annotated resources
WWW Virtual Library http://www.vlib.org/
The first subject directory on the Web. Features comprehensive,
well-annotated subject collections maintained by experts around
the world
Subject directories—Popular
• Google Directory http://directory.google.com/
• Yahoo! Directory http://dir.yahoo.com
Both Yahoo! and Google offer popular directories. They are not very selective,
but they offer some wonderful subject collections.
Examples:
Yahoo! Full Coverage
http://fullcoverage.yahoo.com/fc/
Google Social Issues
http://directory.google.com/Top/Society/Issues/
Instead of looking through the
categories in a search directory, you
can put in your terms in their search
bar, but it will only look through the
sites that have been included within
that directory—not the entire web,
unless indicated.
Metasearchers-• Sends your search terms to several other
search engines at once.
• Gives an overview of a topic across the
Internet.
Examples:
• Profusion
• Dogpile
• Metacrawler
Remember….
• Hits are returned and ranked according to-•
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How
How
How
How
many times terms appear on the page
often terms appear
close terms are to each other
near the top of the page the terms are found
• The best results will appear on the first page
or two of hits
• No two search engines are alike. Try another
search engine, or rephrase your terms if you
don’t get good results.
More Searching Help-• 7 Steps to Better Searching
Your Goal as a Searcher:
“Upping” the best results
Traditional
• Text relevance
Second generation
• Link analysis
• Popularity
• Thesauri
• Visualization/Mapping
• “More like this”
• Concept clustering/
Autocategorization
Trends to look for
• SurfWax and Ask Jeeves use
indexes or thesauri. The
burden of coming up with
precise or extensive
terminology shifted from
searcher to the engine.
• Google, Teoma, Wisenut rank
results based on the behavior
Specialized Search Tools
• Scirus (science search)
• Search.edu (searches only edu domains)
• Biography Center (profile aggregator)
• SearchEric.org (education)
http://searcheric.org
• SOSIG (Social Sciences)
http://www.sosig.ac.uk/
• HUMBUL (Humanities)
http://www.humbul.ac.uk/
Invisible/Deep/Hidden Web
• The Web’s largest growing resource
• Estimated to be 40 times size of the
visible Web
• Most not subject to fees
• Includes topic-specific databases
Why is some of the Web invisible?
• The material is on the Web but it is a
proprietary database
• The material is on the Web but is in a free
database
• Content appears past the page size reach of
the crawler
• The crawler does not search a particular file
format or non-text interface
• The page is available only after registration
• The page is available by some engines but not
others. No two engines are the same
Why is some of the Web invisible?
(2)
• Time lag exists between posting, crawling,
and searching (Spiders do not crawl in real
time). Site may have been unavailable during
the last crawl
• Firewall prevents access
• Page must be accessed or searched in a
special way
• Page is not linked to from any other page
• Page was not submitted to the search engine
you are using
Tools for seeing the Invisible Web
• Invisible Web Directory
http://invisible-web.net/
• Complete Planet
http://completeplanet.com
• Librarian’s Index to the Internet
http://lii.org
• Pinakes
http://www.hw.ac.uk/libWWW/irn/pinakes/pinakes.html
• OAIster
http://oaister.umdl.umich.edu
Examples of Free Databases
• Find Articles
http://www.findarticles.com
• MagPortal
http://magportal.com
• ERIC
http://searcheric.org
• American Memory Collection Finder
http://lcweb2.loc.gov/ammem/collections/finder.html
• NARA
http://www.archives.gov/search/index.html
• Perry Casteñeda Map Collection
http://www.lib.utexas.edu/maps/index.html
The free Web is
not enough!
What’s not on the free Web?
• Copyrighted fiction and nonfiction:
biographies
• High quality reference: including
literary criticism, science biography
• Full, searchable archives of
journals, magazines, newspapers
• Most of our OPAC