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Effective searching Evaluating results! Understanding strategy/

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1 Effective searching Evaluating results! Understanding strategy/
syntax Brainstorming/ Questioning/ Planning Choosing the right type of search tool Evaluating results! Staying up to date These are some of the skills effective searchers use. Why are each of these important?

2 Choosing the right search tool is an important strategy!
search engines annotated/rated directories subject directories subject guides/gateways You have more choices than you may realize! meta-search tools specialized directories

3 A field guide to the search tools
Search engines Databases of billions of Web pages, gathered by automated “robots,” allowing broad, often overwhelming searches. Search engines vary in 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. Can you name examples of any of these tools?

4 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 Can you give a specific example of when a subject directory might be your best choice?

5 Two Essential Directories
Librarians’ Index to the Internet Well-organized, selective, and continually updated collection, also known as “the thinking person’s Yahoo.” Maintained by a team of librarians at Berkeley Public Library Kids Click Great starting point for kids. Annotations are carefully written. Offers grade levels and describes how illustrated a site is.

6 Subject directories to count on
INFOMINE: Scholarly Internet Resource Collections A large collection of scholarly Internet resources 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 Great for high school and college research BUBL Link This UK project leads to carefully selected and annotated resources WWW Virtual Library The first subject directory on the Web. Features comprehensive, well-annotated subject collections maintained by experts around the world Demonstrate a few of these directories.

7 Subject directories—Popular
Google Directory Yahoo! Directory Both Yahoo! and Google offer popular directories. They are not very selective, but they offer some wonderful subject collections. Examples: Yahoo! Full Coverage Google Social Issues You can demonstrate the value of using these directories by showing Google’s Issue page or a couple of Yahoo’s Full Coverage news pages

8 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. Can you give a specific example of a time when search engines are the best way to approach a search?

9 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 Search engines do not find every document on the Web. They vary in “freshness,” or how frequently they update their databases. Sometimes they may find a site’s homepage but not a page buried deep in its links. They vary in how fully they search the words of a Web page. Sponsored results can divert searchers from the “good stuff.”

10 When using a search engine
Your goal is to get the best stuff to appear on the first two or three pages. Be real! You’ll never notice the really great site listed on page 15!

11 Relevance rocks! Search engines determine relevance in different ways.
Relevance is the way in which search engines determine which hits or results get to the top of their lists.

12 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

13 Some search tools present results horizontally, not in long lists!
Query Server (metasearch) Vivisimo (metasearch) Demonstrate results for a major subject, for instance “Civil War.” Instead of the page-after-page vertical results produced in traditional engines, these tools bring many options up to the front page of a search.

14 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 of millions of Web users. Vivisimo,Teoma, and WiseNut use concept clustering/autocategorization/horizontal display Kartoo maps results visually Ixquick Metasearch compiles “top ten” lists of the major engines

15 Specialized Search Tools
Scirus (science search) Search.edu (searches only edu domains) Biography Center (profile aggregator) SearchEric.org (education) SOSIG (Social Sciences) HUMBUL (Humanities) If you know of a specialized search engine, that might be the first place to begin a search. Demonstrate the advanced screen of Scirus (

16 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

17 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 Proprietary databases are not free to the public. You subscribe to be able to access them. A crawler (or a spider) is a little computer program sent out by a search engine to find results.

18 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

19 Tools for seeing the Invisible Web
Invisible Web Directory Complete Planet Librarian’s Index to the Internet Pinakes OAIster Demonstrate the resources listed on a few of these directories.

20 Examples of Free Databases
Find Articles MagPortal ERIC American Memory Collection Finder NARA Perry Casteñeda Map Collection

21 The free Web is not enough!

22 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

23 GALENET GALILEO

24 Some special search tools for kids
Ask Jeeves for Kids KidsClick! (highly selective) Yahooligans Multnomah County Library Ithaki Kids Metasearch

25 Tools to help you make search engine choices:
Debbie Abilock’s Choosing the Best Search For Your Purpose /information/5locate/adviceengine.html How to Choose a Search Engine or Directory (U. Albany) For more information (and for people who love searching): Search Engine Watch

26 The Importance of Search Terms and Key Words

27 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* adolesc* marijuana program* success child* alcohol treat* Here’s another pre-planning chart. ANDs, or ideas to combine, run horizontally. ORs, or related terms, run vertically. Note that stemming, truncation, or wildcards will pick up different forms of words so you don’t have to type all spelling possibilities for the same concept.

28 How important AND is!!! AND requires that both or all search terms appear in your results! AND narrows your search. The green portion is the part of the search that included results that had both search terms. AND is the Boolean operator you need most, especially when searching subscription databases. Different search tools express AND in different ways. Sometimes you may use a +. Sometimes you may select “all the words.” More and more search engines like Google assume an AND and you do not need to express it. With most online, subscription databases it is very important to express AND.

29 When do you really need OR?
Use OR cautiously! OR expands your search. The yellow portion shows that OR included either term. OR can make it so large that it may be unmanageable. Note: Google now looks for synonyms when you put a tilde (~) directly in front of a word. Example: ~boat OR is generally used for synonyms or related words.

30 Use NOT as a refinement technique when problem words are likely to come up eagles NOT Philadelphia “Martin Luther” NOT King The yellow portion is the search with the word “football” excluded. Can you think of other problem examples when you might use NOT? NOT may sometimes be expressed with a - sign. Some advanced screens allow you to use NOT, by providing lines for you to type words you want to exclude.

31 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 What did AND do to our search? Can you see how this Boolean operator works to focus or narrow your search? (You might try this again using ORs.)

32 “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 would happen if you searched for vitamin A without the quotation marks? Can you come up with examples of other terms that should absolutely be searched as phrases?

33 Advanced Search Screens
Google All the Web AltaVista HotBot Advanced search screens allow searchers greater power to really focus a search, and often to easily search within fields. (Show how to get to these advanced screens and what options they offer. Ask students for specific examples of how they might use them.)

34 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 Search Engine Watch’s Features Chart gives searchers an idea of which search features are available and what syntax is used in each major search engine. (You might want to define field searching.) Databases are composed of fields. You may have the option of searching the title, subject, date, or file format fields among several others.

35 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 Can you think of specific examples of when field searching would be important? Why would a title search be helpful? Why would a link check help you evaluate a site? When would it be useful to search by domain? Demonstrate where students might find these strategies in a few advanced search screens.

36 Cite your sites!

37 Let’s review Okay, what did we learn?
Ask students to go through what they learned about search tools as a review.


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