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
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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. 2
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
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The Internet is a global network of computers.
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The World Wide Web is a service running on the Internet.
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it is the name given to a collection of documents stored on computers connected to the Internet
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these documents are written in a markup language (usually HTML) and characterized by ‘hypertext links’ 5
Key Terms Defined
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A web browser is a piece of software.
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its purpose is to read and display web pages 6
Key Terms Defined
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To search the web, we use search tools accessed via web pages.
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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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Web browser software interprets HTML and displays page HTML tags define document structure
What to know: Web concepts 2. Know the basic types of general purpose search tools and how they work.
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search engines versus subject directories 9
Basic Web Search Tools
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Both Subject Directories and Search Engines offer access via a web page to a database of information about web sites.
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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
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A subject directory searches a human compiled database of web sites, organized into subject categories.
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The database includes the name and URL of the web site, plus a brief description.
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The database does NOT include individual web pages within the site. 11
Search Engines
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A search engine searches a computer compiled database of information about individual web pages. There are no subject categories. No human examines the web sites.
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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. 12
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.
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Web sources must be carefully evaluated.
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Everything is NOT on the Web.
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There is no such thing as a ‘live’ Web search.
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There is no such thing as a fully comprehensive Web search.
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3 Essential Practical Things to Know About General purpose 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
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Search keywords here E.g., Yahoo!
Or browse subject categories here 18
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 20
Yahoo Directory Site 21
Google Directory 22
Example
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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.’ 28
Basic ‘Search Syntax’ Searching Phrases “” searches enclosed terms as a phrase
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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 32
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)
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allows for 5 characters at end of word
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use to search plurals / alternate endings
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e.g., computer* retrieves ‘computers,’ ‘computerized,’ etc.
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Advanced Search Syntax
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Field searching
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Format:
fieldname:TERM
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Advanced Search Syntax
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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) 38
Example
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Search for Canadian federal election results.
“federal election” domain:ca
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retrieves documents containing BOTH the phrase “federal election” in the text, and the domain “ca” in the web address 39
Example
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Search for a good list of international phone directories.
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we already know a good Canadian online phone directory
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strategy: see what other sites link to it
link:canada411.sympatico.ca
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Google Search 41
Google Search 42
Google Search 43
Listing of Web Phone Dirs.
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Google Advanced Search 45
General-purpose Search Tools 3. Know where to go to learn more quickly.
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what search tools are out there?
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what are their advanced features?
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where do they get their results?
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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
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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 55
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 57
Search for general topic, to find source 58
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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
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Ask Who cares about this?
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Rather than searching for the info needed, find out if someone has already gathered it together for you
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identify a likely organisation and its web site
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use specialised tools to find ‘guru pages’ and subject guides 66
Strategy: Who cares?
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Is there an organisation or person interested in this problem?
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Is there a government agency responsible for collecting or disseminating this info?
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Would a trade association be interested on behalf of its members?
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Has a university department or independent scholar or hobbyist created a subject guide?
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Example
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Where can I find coal production statistics for the US?
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Example
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Where can I find coal production statistics for the US?
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Who cares?
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United States Geologic Survey (USGS)
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often government agencies are responsible for compiling statistics 69
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.
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collect sites useful for searching your subject area
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develop a workable way to organise and access them 72
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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
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3 Essential Conceptual Things to Know about the Web:
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Know what it is; know basic definitions and components involved.
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Know that there are two basic types of general-purpose search tools, and how they work.
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Bear in mind implications of structure for how searches work, and limitations of the Web.
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Summary
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3 Essential Practical Things to Know about General Purpose Search Tools:
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Know when directory results may be more useful than search engine results, and vice versa.
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Know advanced search features and syntax, such as ‘search engine math.’
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Know where to go to quickly learn more.
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Summary
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3 Essential Useful Tips to Know About Search Strategy:
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Consider using general-purpose search tools to search for sources, not for directly for content.
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Find expert sources by asking yourself, Who cares about this topic?
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Build a core collection of specialised search tools beyond general-purpose subject directories and search engines.
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