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Ixquick:  Searches AltaVista, Fast Search, Excite, HotBot, Infoseek, MSN, Yahoo & more

Why Cover Both Topics?

• Most people use search engines without considering the usefulness of subject directories for their topics.
• The difference between these two types of tools is poorly understood.
• Yahoo! is such a popular directory that often more selective and higher quality directories are often
  overlooked.
• Try out multiple sites when investigating a topic. They vary in their database contents, features,
  selectivity, and accuracy.

Subject Directories

• Entries chosen by people
• Ordered by subject
• Some have annotations and/or ratings
• Small subset of the Internet
• Most are searchable
• They vary significantly in selectivity

Academic and Professional Directories

• Created by librarians or professionals in the field
• Tend to be associated with libraries and academic institutions
• Created to enhance the research process
• Careful selection process is applied
• Do not generate income or carry advertising

Commercial Directories/Portals

• Created to generate income
• Links to a wide range of topics and often emphasize entertainment, commerce, hobbies, sports, travel,
  and other interests not necessarily covered by academic directories
• Sites seek to draw traffic in order to support advertising
• Yahoo is an example of a commercial portal

When should directories be used?

• When broad idea of topic is to be researched

• When want to see sites on topic often recommended and annotated by experts

• When want to retrieve a list of sites on a topic, rather than numerous individual pages contained within these sites

• When want to avoid viewing low-content documents that often turn up on a search

Search Engines

• Database built by computers
• Comprehensive
• No evaluation
• Use relevancy rankings
• Some have advanced search options

Database Creation: Search Engines

• Web Spiders (robots, crawlers) search Web servers
• Frequent visits to sites that change often
• Visit some of all pages on a Web site
• Takes from two weeks to …
• Adds to and alters its database
• Stores information in records and fields according to differing indexing schemes

Data not found in Search Engines

• Dynamic data e.g. a CGI form request
• Content of PDF, other formatted files
• Content of most sites requiring a login
• Content of most databases

  Estimated to be 40-60% of Web pages

  Examples:
  • Library Online Catalogs
  • Martindale Hubbell 
  • Medline
  • IRS forms
  • Government Statistics

When should search engines be used?

• When have narrow idea of obscure topic or idea to research
• When want to search the full text of millions of pages
• When want to look for particular types of documents, file types, source locations, languages, date last
  modified, etc.
• When want to take advantage of newer retrieval technologies such as concept clustering, link raking, etc.

Keyword
A search type in which you enter the terms representing the concepts you wish to retrieve
Break down topic into component concepts

• List keywords for each concept
• List synonyms
• Specify the logical relationships among keywords (Boolean logic)

Basic Search Operators

• Operators must connect to a word or phrase, no spaces, e.g. +python* -”monty python"
• + Plus sign to include
• - minus sign to exclude
• " " Quotes to phrase (2 or more words)
• * to truncate

These work in many, but not all Search Tools

Boolean Searching

• AND; find both of the words
• kayak AND canoe
• OR; find either or both of the words
• kayak OR canoe
• NOT; find the first word not the second word
• kayak NOT canoe

NOTE: by default, some tools use AND some use OR

Truncation
Terms that have been shortened to their root

nation* retrieves
• nation
• nations
• nationality
• nationalization

Nesting
Combining several terms and operators into a single “search statement”
When more than one operator is used, parenthesis should be used to clearly distinguish how terms are to be
grouped.

• History AND (England OR Great Britain)
• Acid (rain or precipitation)

Usenet New Groups
Google Groups (a full-text search tool), http://www.deja.com -- a specialized database just for searching
Newsgroups.

• Browse by subject category or “community” at left
• Search for terms in newsgroup discussion or communities in the search box

Before You Click

• Should I use the Internet?
• What’s my subject?
• What are my search terms?
• What search operators to use?
• Which tool should I try first?
• Should I add or delete a term?

Searching Strategy

• Try a logical guess
• Pick a search tool
• Choose keywords
• vary your spelling
• know how to widen your search

Know when to move on

• Try more than one tool
• Search results vary widely
• What you see is less than what’s out there
• Question authenticity
• Remember, success depends on matching words and phrases with what’s out there

404 File Not Found Problems

• Your typos
• Good to look before you click search button
• Their typos in links
  • e.g. berkley instead of berkeley
• Directory/file renamed or moved
• Move up a level or two and look around
• If you really want it; title search in AltaVista or NorthernLight

Remember…

• The Internet is a self-publishing medium
• Your searches will yield files of varying quality
• Be sure to evaluate everything you encounter
  

updated 12/00