Transcript WEB SEARCHING Part One - Community informatics

What to Know:
9 Essential Things to Know
About Web Searching
Janet Eke
Graduate School of Library and Information Science
University of Illinois at Champaign-Urbana
2003
Topics
• 3 Essential Conceptual Things to
Know About the Web.
• 3 Essential Practical Things to Know
About General-purpose Search Tools.
• 3 Essential Useful Tips to Know About
Search Strategy.
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3 Essential Conceptual
Things to Know About the
Web
What to know: Web concepts
1. Understand basic context and
structure.
Know what the World Wide Web is.
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Key Terms Defined
• The Internet is a global network of
computers.
• The World Wide Web is a service
running on the Internet.
– it is the name given to a collection of
documents stored on computers connected to
the Internet
– these documents are written in a markup
language (usually HTML) and characterized
by ‘hypertext links’
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Key Terms Defined
• A web browser is a piece of software.
– its purpose is to read and display web pages
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Key Terms Defined
• To search the web, we use search tools
accessed via web pages.
– Search tools may be as simple as a list of
links, or as complicated as a large database
of information gathered from web pages.
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HTML tags
define
document
structure
Web browser
software
interprets
HTML and
displays page
What to know: Web concepts
2. Know the basic types of generalpurpose search tools and how they
work.
– search engines versus subject directories
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Basic Web Search Tools
• Both Subject Directories and Search
Engines offer access via a web page to
a database of information about web
sites.
• The information in their databases,
however, and the way this information
is gathered, organized and maintained,
is very different.
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Subject Directories
• A subject directory searches a humancompiled database of web sites,
organized into subject categories.
• The database includes the name and
URL of the web site, plus a brief
description.
• The database does NOT include
individual web pages within the site.
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Search Engines
• A search engine searches a computercompiled database of information about
individual web pages. There are no
subject categories. No human examines
the web sites.
• The database includes detailed
information from the web site -- in some
cases every word on every page is
indexed; in others only selected portions
are indexed.
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Directories VS Engines
UI LIS Current Clips: http://www.lis.uiuc.edu/clips/2002_12.html
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What to know: Web concepts
3. Bear in mind the implications of the
structure of the Web environment and
its search tools.
–
–
–
–
Web sources must be carefully evaluated.
Everything is NOT on the Web.
There is no such thing as a ‘live’ Web search.
There is no such thing as a fully
comprehensive Web search.
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3 Essential Practical Things
to Know About Generalpurpose Search Tools
General-purpose Search Tools
1. Know when directory results may be
more useful than search engine results,
and vice versa.
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Directories VS Engines
UI LIS Current Clips: http://www.lis.uiuc.edu/clips/2002_12.html 17
E.g., Yahoo!
Search
keywords here
Or browse subject
categories here
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Search Results: 5 types
Types of results
Yahoo Directory category
matches
Blends site results from
Google and Yahoo
Directory
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Search Results: Directory only
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Yahoo Directory Site
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Google Directory
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Example
• Find major earthquake engineering
research centres.
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Category view
Annotated
directory entries
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General-purpose Search Tools
2. Know advanced search features and
syntax, such as ‘search engine math.’
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Basic ‘Search Syntax’
Searching Phrases
“” searches enclosed terms as a phrase
• Example:
Find source and completion of quotation
beginning: “went down to the station to look
for her there”
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Without Quotation Marks
First results NOT relevant.
Terms are scattered in
documents.
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Search terms as a phrase
Enclose terms in
quotes to search
as a phrase.
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Full album is in one web page
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Use browser to search page
Use browser to search page
Use browser to search page
Basic Search Syntax
+
*
-- include term
-- exclude term
-- truncation symbol (AltaVista)
– allows for 5 characters at end of word
– use to search plurals / alternate endings
– e.g., computer* retrieves ‘computers,’
‘computerized,’ etc.
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Advanced Search Syntax
• Field searching
• Format:
fieldname:TERM
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Advanced Search Syntax
• Field Searching Examples
title:drucker searches for ‘drucker’ only in title
of web page (Google: intitle)
url:hoovers searches for ‘hoovers’ anywhere in
the web address (Google: inurl)
domain:ca searches for ‘ca’ (canada) only in the
domain portion of the web address
link:www.hoovers.com searches for pages that
link to www.hoovers.com
lyrics site:j-tull.com searches for the word
‘lyrics’ within the site www.j-tull.com (Google)
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Example
• Search for Canadian federal election
results.
“federal election” domain:ca
– retrieves documents containing BOTH the
phrase “federal election” in the text, and the
domain “ca” in the web address
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Example
• Search for a good list of international
phone directories.
– we already know a good Canadian online
phone directory
– strategy: see what other sites link to it
link:canada411.sympatico.ca
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Google Search
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Google Search
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Google Search
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Listing of Web Phone Dirs.
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Google Advanced Search
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General-purpose Search Tools
3. Know where to go to learn more
quickly.
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–
–
–
what search tools are out there?
what are their advanced features?
where do they get their results?
is there a more specialised search tool for my
topic?
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Search Engine Watch
www.searchenginewatch.com
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Search Engine Watch
www.searchenginewatch.com
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Search Engine Watch
Search Features Charts
http://www.searchenginewatch.com/facts/ataglance.html
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Search Engine Showdown
www.searchengineshowdown.com
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Search Engine Showdown
Search Tool In-depth Reviews
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3 Essential Useful Tips to
Know About Search
Strategy
Search Strategy
1. For some topics, consider using
general-purpose search tools to search
for sources, not for directly for content.
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Example
• What is the provenance of the
Leonardo da Vinci painting “Virgin of
the Rocks” in the National Gallery
(UK)?
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Direct search in Google
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Direct search in Google
Results may be useful. Need to
examine and evaluate individually.
No source stands out as useful for
future provenance searches.
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Search for general topic, to find
source
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Search for general topic, to find
source
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Search Strategy
2. Find expert sources by asking
yourself, Who cares about this topic?
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The ‘Who Cares?’ strategy
• Ask Who cares about this?
– Rather than searching for the info needed,
find out if someone has already gathered it
together for you
• identify a likely organisation and its web site
• use specialised tools to find ‘guru pages’ and
subject guides
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Strategy: Who cares?
• Is there an organisation or person
interested in this problem?
– Is there a government agency responsible for
collecting or disseminating this info?
– Would a trade association be interested on
behalf of its members?
– Has a university department or independent
scholar or hobbyist created a subject guide?
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Example
• Where can I find coal production
statistics for the US?
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Example
• Where can I find coal production
statistics for the US?
• Who cares?
– United States Geologic Survey (USGS)
– often government agencies are responsible
for compiling statistics
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Government Agency
US Geologic Survey
publishes the
Minerals Yearbook.
Sample: Coal Product
statistics
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Search Strategy
3. Build a core collection of specialised
search tools beyond general-purpose
subject directories and search engines.
– collect sites useful for searching your subject
area
– develop a workable way to organise and
access them
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http://www.census.gov
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Powermarks bookmark utility -- creates
searchable database of bookmarked
sites; easy to organise, weed, and search.
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Powermarks bookmark utility -- creates
searchable database of bookmarked
sites; easy to organise, weed, and search.
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Summary
• 3 Essential Conceptual Things to
Know about the Web:
– Know what it is; know basic definitions and
components involved.
– Know that there are two basic types of
general-purpose search tools, and how they
work.
– Bear in mind implications of structure for
how searches work, and limitations of the
Web.
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Summary
• 3 Essential Practical Things to Know
about General Purpose Search Tools:
– Know when directory results may be more
useful than search engine results, and vice
versa.
– Know advanced search features and syntax,
such as ‘search engine math.’
– Know where to go to quickly learn more.
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Summary
• 3 Essential Useful Tips to Know About
Search Strategy:
– Consider using general-purpose search tools
to search for sources, not for directly for
content.
– Find expert sources by asking yourself, Who
cares about this topic?
– Build a core collection of specialised search
tools beyond general-purpose subject
directories and search engines.
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