Transcript Slide 1

Searching and Evaluating
Public Web Resources
and
Electronic Library Resources
THE FREE WEB VS. THE LIBRARY
The “public web” vs. “electronic library resources”
Two kinds of Internet or Web information are
• the "free Web" is accessible through search tools such as Google
or Yahoo
• the "invisible Web" (Electronic Library Sources) is accessible
through library purchased contracts with content providers, with
article databases such as ProQuest and Ebsco.
The public (“Free”) Web
(We all know what that is, don’t we??)
Information on the World
Wide Web is:
• widespread
• convenient
• diverse
• abundant
• a preferred method
of student research
But it can also be:
• hard to find
• unevaluated
• lacking quality
• irrelevant
• incomplete
• not appropriate
• costly
• constantly changing
Electronic Library Sources
(What are they?)
To access your library resources, go to this site:
http://www.atl.devry.edu/CampusLibrary/
• Electronic library sources (the “invisible web”) are sources often originally
in print though they are now in electronic form.
• Examples include:
 the
library catalog
 article databases, such as ProQuest and EbscoHost
 electronic reference sources, such as netLibrary and
Encyclopedia Britannica
• Some electronic library sources advantages:
 indexing
 citations
 abstracts
 full-text
articles
• Librarians can assist users in locating appropriate resources, whether print
or electronic, and provide in-depth guidance for research assignments.
Electronic Library Sources: Advantages
• SELECTION: Library resources are evaluated and selected by librarians for their
reliability and authority. While the Web clearly contains reliable and authoritative
information, anyone with access to Web space and create a site and mount it for display
and access. There is no quality control on the Web.
• AUTHORITY: Library provided electronic resources are compiled by professionals and
evaluated for purchase or use on that basis.
• ACCESS: Library users affiliated with an institution have access to the library's electronic
resources. Libraries subscribe to high quality resources for a fee and therefore restrict
usage to qualified users. Freely available Internet information may only sometimes be
high quality, and are sometimes questionable.
• OBJECTIVITY: Some search engines and websites order your search results based on
how much a person or group has paid to have their site included in the search for
particular words. Library electronic resources will provide primarily an unbiased selection
of information sources to choose from, allowing you to make the judgment call.
• INDEXING AND ORGANIZATION: Most publicly accessible search tools use only
keyword searching. Because the Web is so immense, it is virtually impossible for
someone to organize every document into a logical structure and provide multiple access
points (title, author, subject, etc.). Library provided resources are purchased from
vendors who supply high quality and consistent content utilizing sophisticated indexing.
The Web or the Library?
Strengths of the Public Web
• to obtain information on colleges,
museums, non-profit organization, or
companies
• for very current information such as
news, sports scores, weather, stock
quotes
• to research a well-known event or
individual particularly if they are recent
• to use online job postings, shopping,
auctions, or travel services
• for opinions on a topic
Strengths of the Library
• to find articles in scholarly journals
• to find articles published in popular
magazines
• to search databases that index articles
in many academic disciplines
• to find books on your topic
• to locate the full-text of articles or
books that are copyrighted
Electronic Library Resources
• To access your library resources, go to this site:
http://www.atl.devry.edu/CampusLibrary/
• See the link of “Electronic Resources” in the left column –
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note the many databases
Start with GALILEO
Off-campus, use your GALILEO password:___________
Try PROQUEST and ESCOHost first for full-text journal
magazine and newspaper articles
Next, try the tabs at the top for GALILEO databases in your
field and on your subject
Usually when you click on a subject area, it will recommend
a database: try this one first. It is usually the largest and
includes the most resources.
EVALUATING
SOURCES
EVALUATING SOURCES
Evaluation Criteria #1 for
Print or Electronic Sources
Ask yourself:
Is the source:
• AUTHORITATIVE?
• RELIABLE?
• WELL-KNOWN?
• WELL-SUPPORTED?
• BALANCED TONE?
• CURRENT?
START
Evaluating Information Sources
Evaluation Criteria #2
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S – Scope
T – Treatment
A – Authority
R – Relevance
T - Timeliness
Adapted from: Iannuzzi, Patricia, Charles T. Mangrum II, Stephen S. Stichart, Teaching
Information Literary Skills, Boston: Allyn & Bacon, 1999.
START
SCOPE
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Are all aspects of the topic covered?
Is the coverage in depth or basic?
Does the information add new or unique information about your topic?
Are there graphics or visual aids that enhance the text?
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Is the information presented as fact or opinion?
Is evidence provided?
Are conclusions logical? Are there links to more information or references?
Is the information free from bias?
Is the information consistent with information from other sources?
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Are the author’s qualifications presented? Is the page signed?
Is there any information about the author available?
Does the author have an educational background related to the topic?
Does the author have other expertise related to the topic?
Is the author affiliated with an educational institution or other reputable organization? Is .edu
part of the URL? Is .gov part of the URL?
Is the information from a web site for an organization that is reliable? Do you know anything
about the reputation of the organization? Is there any information on the page about the
organization?
TREATMENT
AUTHORITY
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RELIABILITY
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Does the information address your topic? Is it appropriate for what you are doing?
Does the information provide evidence for your point of view?
Does the information verify other information you are using from other sources?
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Is there a date provided for the web page and the information on it?
Is the information sufficiently current for your purpose?
Regardless of the date, is the information still useful?
TIMELINESS
EVALUATION CRITERIA #3, 4, 5,…
WEBSITES ON EVALUATING WEB RESOURCES
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Evaluating Quality on the Net
Hope Tillman (2003) < www.hopetillman.com/findqual.html > [6 Feb 04]
A systematic approach to searching on the net and critically evaluating the data
Evaluating Information Found on the World Wide Web
Ernest Ackerman and Karen Hartman (2003) < www.webliminal.com/search/search-web12.html > [6 Feb 04]
Internet evaluation guidelines, activities, and links
• Evaluating What You Have Found
University of Waterloo < www.lib.uwaterloo.ca/libguides/1-2.html > [6 Feb 04]
Includes useful questions to ask when evaluating a Website
• Search Engine Showdown
Greg Notess (2003) < www.searchengineshowdown.com/ > [6 Feb 04]
Search Tools
• Search Engine Showdown, the users' guide to Web searching, compares and evaluates Internet search engines
from the searcher's perspective. Developed originally as a way to keep track of search engine features and
search capabilities and to share that information with others, the site has grown to include: Search engine
features chart, detailed search engine reviews, an online newsletter, statistical analysis, and search strategies.
• 10 Reasons Why the Internet is No Substitute for a Library
Mark Y. Herring (2001) < www.ala.org/ala/alonline/selectedarticles/10reasonswhy.htm > [6 Feb 04]
The viewpoint of a college library dean:
• Info Lit for Faculty; Thomas G. Kirk, Jr. (2003) <
www.ala.org/ala/acrl/acrlissues/acrlinfolit/infolitoverview/infolitforfac/infolitfaculty.htm > [6 Feb 04]
A brief
guide provides an introduction to the concept of information literacy and model information literacy programs.
It is designed specifically for academic administrators and faculty.
• Evaluating Web Pages
UC Berkeley (2004) < www.lib.berkeley.edu/TeachingLib/Guides/Internet/Evaluate.html > [6 Feb 04]
Techniques to apply and questions to ask when using Web pages for assignments
General
The complete reference source for APA style.
• APA Documentation Style
APA < www.apastyle.org > [1 Apr 04]
• Search Engines!
< www.searchengineshowdown.com > [28 Jun 04]
WEB ACTIVITY # 1
Place in your Daily Work Portfolio and post in Threaded Discussions
• At your class website: http://kareyperkins.com/classes/135 find
the two web evaluation activities. Do the first activity; put it in your
daily work portfolio and post it also in threaded discussions:
• WEB EVALUATION ACTIVITY #1: Visit both of the following
websites. Choose one form of evaluation criteria for sources, such
as the START criteria or others discussed in the presentation or from
one of the websites in the Webliography. Evaluate the two sites
below. While both may present useful information, is it important
for students to be able to recognize the biases that some sites
present?
• NCPA - Crime and Gun Control -
http://www.ncpa.org/bothside/crime.html
• Gun Control vs. Gun Rights -
http://www.opensecrets.org/news/guns/index.htm
EVALUATING
SEARCH ENGINES
What Makes a
Search Engine Good?
All search engines consist of three parts:
(1) a database of web documents
(2) a search engine operating on that
database
(3) a series of programs that determine
how search results are displayed
Because the search engine business is competitive, most
search engines also offer additional features that are
convenient or fun. The table below shows what can vary
within each of the three basic parts in search engines
1. Database of web documents/size
How many documents does the search engine claim it has?
How much of the total web are you able to search?
Freshness ("up-to-dateness"):
• Search engine databases consist of copies of web pages and other documents that
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were made when their crawlers or
spiders last visited each site. How often is the database refreshed to find new pages?
How often do their crawlers update the copies of the web pages you are searching?
Completeness of text:
• Is the database really "full" text, or only parts of the pages?
• Is every word indexed?
Types of documents offered:
• All search engines offer web pages.
• Do they also have extensive PDF, Word, Excel, PowerPoint, and other formats like
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WordPerfect?
Are they full-text searchable?
Speed and consistency:
• How fast is it?
• How consistent is it? Do you get different results at different times?
• Is there a "family" filter? Does it work well? Is it easy to turn on or off?
2. The search engine's capabilities
All search engines let you enter some keywords and search on them. What happens inside?
Can you limit in ways that will increase your chances of finding what you are looking for?
Basic Search options and limitations:
• Automatic default of AND assumed between words?
• Accepts " " to create phrases?
• Is there an easy way to allow for synonyms and equivalent terms (OR searching)? Can you OR
phrases or just single words?
Advanced Search options and limitations:
• Can you require your search terms in specific fields, such as the document title? Can you require
some words in certain
• fields and others anywhere?
• Can you restrict to documents only from a certain domain (org, edu, gov, etc.)? Limit to more
than one or only one?
• Can you limit by type of document (pdf or excel, etc.)? More than one?
• Can you limit by language?
• How reliably and easily can you limit to date last updated?
General limitations and features:
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What do you have to do make it search on common or stop words?
Maximum limit on search terms or on search complexity?
Ability to search within previous results?
Can you count on consistent results from search to search and from day to day?
Can you customize the search or display?
3. Results display
All search engines return a list of results it "thinks" are what you are looking for.
How well does it "think like you expect it think"?
Ranking:
• Are they ranked by popularity or relevancy or both?
• Do pages with your words juxtaposed (like a phrase) rank highest?
• Do you get pages with only some of your words, perhaps in addition to pages with
them all?
Display:
• Are your keywords highlighted in context, showing excerpts from the web pages
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which caused the match?
Some other excerpt from the page?
Collapse pages from the same site:
• If it shows only one or a few pages from a site, does it show the one(s) with your
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terms?
How easy is it to see all from the site?
Can this be changed and saved as your preferred search method?
4. Other features
• Search engine designers try to come up with all kinds of features and services that
they hope will allure you to their services.
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Joe Barker, Copyright 2003
The Public Web:
Using a Variety of Search Engines
• Different search tools give different results.
• A comprehensive search requires the use of more than one
search tool.
• Overlap between the various search engines is surprisingly
low.
• This is due to each search engine indexing only a portion of
the web and no two indexes being the same.
• Current estimates are that the largest search engines index
only 20-30% of the indexable web.
• Search engines may also index the same sites differently,
and the different search syntax will yield different results.
SEARCH ENGINES
AltaVista http://altavista.digital.com/
• one of the first major search engines, started in 1994 by Digital
Equipment Corporation.
• searches millions of documents including newsgroups.
• gives control over the format of your results
• provides both a simple and advanced method of searching.
• phrases can be searched with the addition of double quotes
• useful especially with names of individuals and phrases.
• a powerful search tool particularly with the advanced searching
features utilized such as wildcards, proximity operators, and results
ranking.
• click on the Help button on either the simple or advanced search
screen for detailed explanations. The results are displayed with a
description taken from the web site as well as the web address.
Google http://www.google.com/
• uses sophisticated next-generation technology to produce the right
results fast with every query.
• returns relevant results using an automated method that ranks
relevant websites based on the link structure of the Internet itself.
Meta-Search Search Engines
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also know as multi-threaded engines
search several major engines at once.
do not crawl the Web
do not maintain a database of web pages.
they act as a middle agent, passing on the query
to the major engines
a quick way to determine which engines are
retrieving the best match for your information
need.
Because search engines vary in ability to
interpret complex searches, meta-search engines
work best with simple searches
META-SEARCH SEARCH ENGINES
• Highway 61 http://www.highway61.com/ A very lighthearted
approach to searching. From choosing how thorough you want your
search to just laughing at the concept, this tool searches several
search sites simultaneously to bring you your results.
• MetaCrawler http://www.metacrawler.com This site does a
search on multiple engines simultaneously, compiles the results,
eliminates the duplicates and gives you a ranked list of returns. It's
excellent for getting a quick hit of what's out there.
• Dogpile http://www.dogpile.com/ This metasearch site can go
through 25 Web search engines, more than two dozen on-line news
services or other types of sources, and sort the results by the search
engine that found them. If you just want the facts, this is a good
way to check which search engine works best for you.
• Ask Jeeves! http://www.askjeeves.com An excellent beginner's
site that's also good for general queries. Ask Jeeves leads you
through questions to help narrow your search and also
simultaneously searches six other search sites for relevant Web
pages.
Directory Search Tools:YAHOO
• YAHOO http://www.yahoo.com/ If you know exactly what you're
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looking for, try using Yahoo!. Yahoo! is technically more of a
directory than a search engine. Choose from a hierarchy of broad
terms and continue to narrow your search. Specify a keyword or
set of keywords within a subject area, and Yahoo! will search only
that area of the entire database.
will search categories, titles, and comments to find listings that
contain all of your keywords.
will not pay attention to case (e.g., "Dow Jones" is treated just like
"dow jones")
will stop after it finds 100 matches.
to customize your search, you'll find several options on the Yahoo!
• Search page: search Yahoo's listings, Usenet newsgroups, or Email
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addresses;
specify whether you want matches to contain all of your keywords or at
least one of your keywords;
specify whether your keywords should be considered as substrings or whole
words;
control the number of matches displayed per page.
Miscellaneous and Others
• DejaNews http://groups.google.com/ This portion of
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GOOGLE searches newsgroups only. It is useful for
topics, but also very useful for finding people who have
communicated in newsgroups. The results will allow you
to look at the communication as well as find out the
email address of the individual.
Internet Sleuth http://www.Isleuth.com A 3,000
strong collection of specialized on-line databases, which
can also simultaneously search up to six other search
sites for Web pages, news and other types of
information. It's excellent for highly specialized searches
in any subjects in its detailed directory.
Searching the Web:
Tips and Techniques
Use of Boolean Operators:
WHAT'S A "BOOLEAN"?
• Boolean logic takes its name from British
mathematician George Boole (1815-1864), who
wrote about a system of logic designed to
produce better search results by formulating
precise queries. He called it the "calculus of
thought." From his writings, we have derived
Boolean logic and its operators: AND, OR, and
NOT, which we use to link words and phrases for
more precise queries.
AND
• Connecting search terms with AND
tells the search engine to retrieve
web pages containing ALL the
keywords.
FCC and wireless and
communication
• The search engine will not return
pages with just the word FCC.
Neither will it return pages with the
word FCC and the word wireless.
• The search engine will only return
pages where the words FCC,
wireless, and communication all
appear somewhere on the page.
• Thus, AND helps to narrow your
search results as it limits results to
pages where all the keywords
appear.
OR
• Linking search terms with OR tells the
search engine to retrieve web pages
containing ANY and ALL keywords.
(FCC or wireless or communication)
• When OR is used, the search engine
returns pages with a single keyword,
several keywords, and all keywords.
Thus, OR expands your search results.
Use OR when you have common
synonyms for a keyword. Surround OR
statements with parentheses for best
results. To narrow results as much as
possible, combine OR statements with
AND statements.
• For example, the following search
statement locates information on
purchasing a used car:
(car or automobile or vehicle)
and (buy or purchase) and used
BOOLEAN AND NOT
• AND NOT tells the search engine to retrieve web pages containing one
keyword but not the other. For example, if you are interested in
animals, but not football, try this:
bears and not Chicago
dolphins and not Miami
• The above examples instruct the search engine to return web pages
about bears, NOT about the football team; about dolphins, not web
pages about the "Miami Dolphins" football team.
• Use AND NOT when you have a keyword that has multiple meanings.
The need for AND NOT often becomes apparent after you perform an
initial search. If your search results contain irrelevant results (e.g.,
Saturn the car rather than Saturn the planet), consider using AND NOT
to filter out the undesired websites.
IMPLIED BOOLEAN: PLUS & MINUS
• In many search engines, the plus and minus symbols can be used as
alternatives to full Boolean AND and AND NOT. The plus sign (+)
is the equivalent of AND, and the minus sign (-) is the equivalent
of AND NOT. There is no space between the plus or minus sign and
the keyword.
• NOTE: AltaVista's Simple Search requires the use of plus and
minus rather than AND, OR, and AND NOT.
• +welding +process
• +Saturn -car
• couch sofa
• IMPORTANT: Use AltaVista's Simple Search for implied Boolean
(+/-) searches, and use AltaVista's Advanced Search for full Boolean
(AND, OR, AND NOT) searches.
PHRASE SEARCHING
• Surrounding a group of words with double quotes tells the search
engine to only retrieve documents in which those words appear sideby-side. Phrase searching is a powerful search technique for
significantly narrowing your search results, and it should be used as
often as possible.
• "John F. Kennedy"
• "Walt Disney World"
• "trail of tears“
• For best results, combine phrase searching with implied Boolean (+/-)
or full Boolean (AND, OR, and AND NOT) logic.
• +"heart disease" +cause
• "heart disease" and cause
• The above example tells the search engine to retrieve pages where
the words heart disease appear side-by-side and the word cause
appears somewhere else on the page.
NOTE ON IMPLIED BOOLEAN LOGIC (+/-)
• When a phrase search is combined with additional
keywords using implied Boolean logic (+/-), you must
put a plus or minus sign before the phrase as well as the
other keywords. If the search involves a phrase with no
additional keywords (e.g., "Walt Disney World"), the plus
sign before the quotes is optional.
• Evaluating information found on the Internet is critical to
successful information retrieval. This session will look at
a variety of ways to evaluate Web information.
WEB ACTIVITY # 2
Place in your Daily Work Portfolio and post in Threaded Discussions
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At your class website: http://kareyperkins.com/classes/135 find the two web evaluation
activities. Now do the second activity; put it in your daily work portfolio and post it also in
threaded discussions:
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WEB EVALUATION ACTIVITY #2: Web Search Activity:
Try the following search using the Google search engine.
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1. Type trail of tears in the search box and click the Google Search button.
How many hits? ____________________
Google searched each of the words you entered separately. You probably got close to 400,000
pages. Looking through even a fraction of these is time consuming and frustrating!
This time, enclose your search terms in quotation marks.
2. Type "trail of tears" in the search box and click the Google Search button.
How many hits? ____________________
When you put quotes around trail of tears, it ensured that the words were searched together as a
phrase. You should reduced your total retrieval (hits), by approximately 75%
3. Type "trail of tears" "andrew jackson" in the search box and click the Google Search
button. Be sure to include quotation marks around both phrases.
How many hits? ____________________
Adding the name of Andrew Jackson makes the search more specific. He's the President who
ordered the removal of the Cherokees from lands east of the Mississippi River. You should have
gotten even fewer returns, around 7,000.
4. Finally, click on Google's Advanced Search located at the top of the search page. Your
previous search terms should already be entered in the boxes. Type .edu in the box to the far
right of Domain. Then click the Google Search button.
How many hits? ____________________
By limiting your search to .edu (educational sites), you have narrowed your results to about
1,000 hits. You could also try .org sites or you could add additional terms to refine your results.
Now, let’s go to the library…
• To access your library resources, go to this site:
http://www.atl.devry.edu/CampusLibrary/
• See the link of “Electronic Resources” in the left column – note the
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many databases
Start with GALILEO
Off-campus, use your GALILEO password:___________
Try PROQUEST and ESCOHost first for full-text journal magazine
and newspaper articles
Next, try the tabs at the top for GALILEO databases in your field
and on your subject
Usually when you click on a subject area, it will recommend a
database: try this one first. It is usually the largest and includes
the most resources.
Put in your search terms and see what articles you can find on
your topic.
Play with the search terms and search engines to find the right
kinds of sources and right number of sources.