Evaluation of Search Engines, Part I  ::  LS101
Search Evaluation

SEARCHING: Search Engines and Indexes [We will use the Alta Vista Search Engine for our examples] USE ADVANCED SEARCH MODE for the following examples

ALL Search Engines (including keyword searching on the library catalog or indexes like ProQuest ) may be evaluated by their ability to do the following:

*Note: Each search engine or interface will use different symbols or commands.

1.A. BOOLEAN SEARCHING or Advanced Syntax: Using AND, OR, NOT to Narrow or Expand searches
   ALSO, Implied Boolean Operators   +, and  -    example=   +Endangered Species + tigers

FOR EXAMPLE -

Expands ::  Endangered Species OR Environment    /    
Narrows :: Endangered Species AND Tigers     /      
Narrows :: Endangered Species NOT Birds

B.  WORD ORDER, words put first in a search will rank the results to favor the first word listed

2. TRUNCATION: Allows for variant spelling and expansion of word stems. Usually one of the following keyboard symbols - * , ? , # [Alta Vista uses *]  Some search engines will look for variant spelling automatically.

FOR EXAMPLE - math* will look for math, mathematics, mathematical

- abnormal* will look for abnormal, abnormality. etc

- econom* will look for econom, economy, economist, econometrics

3. NESTING: ( ) Using parenthesis to organize your search terms

4. RELEVANCY RANKING: Even though you might come up 1,000's of "hits" from a search, most search engines will rank the list of hits by a number of conditions: peer ranking, number of times a word is in an document/whether the word shows in the title (meta-tags), first words in search string will rank first, etc.
Note: Some search engines sell placements within their hits list.  See .... @ http://searchenginewatch.com/links/Major_Search_Engines/Paid_Listings_Search_Engines/index.html for more information. 

Link Analysis -Peer Ranking or Popularity Ranking: Most search engines use this kind of ranking.  How many times other web pages link to web site determines its ranking.  Google uses this.  Also, how many times a visitor clicks when at the site will increase a web page rank versus other sites.  For more information go to http://searchenginewatch.com/webmasters/rank.html

Alta Vista (in Advance Search Mode) allows the searcher to rank search results so the words in the title of web sites will come up first in your search results list.

5. PROXIMITY: Very useful for Full Text searching of large documents. In Alta Vista, using NEAR looks for words within 10 words of each other.

FOR EXAMPLE - investment NEAR strategies

(in Alta Vista, the documents that come up will have these words within 10 words of each other in the text)

6.PHRASES: Alta Vista requires that quotations be placed around words you want searched as phrases.

FOR EXAMPLE - "criminal justice"

- "Born to be Wild"

7. CASE SENSITIVITY: if you don't capitalize, it will look for both Upper and Lower Case. If Capital letters are used, it will look only for the Capitalized Letters.

9. Can the search engine search just certain fields ?   Alta Vista can search just the url: , title: , image: , link: , domain:
Go to http://doc.altavista.com/help/search/search_help.shtml   for more fields.

10.  Number of "hits"results or size of search engine.  Go to http://www.searchenginewatch.com/reports/sizes.html for more information

11.  Can one search by material type?  can you search just for images or sound or video, etc.

12. When you are searching, are you searching the web sites "human-filtered" directory or the broader WWW?  How can you tell?

Search Homework    
LETS TRY A SEARCH!!!!:   Print out this page.  Then Go to Alta Vista  URL: GO TO www.altavista.com [You must be in Advanced Search mode]

Search Example #1: A good habit for searching is to write out your search statement and identify searchable terms.  Ranking (Sort By) allows you to choose the order of your results by weighting chosen words.  Try the same search but rank it differently and see what changes

I'm researching the status of Tigers as an endangered species and the habitats they live in.

Search Example #2:

I want to find math textbooks that are used in the elementary grades.

Search Example #3 I want to see if the professional organization I'm affiliated with has an official Web site

Search Example #4

I've heard about "cookies." Apparently they reside on my personal computers hard drive and record where I've "traveled" on the Internet. Find out some information about this and privacy issues.

Question #5
 ---Find a photo of a train located in Vermont
First do a search in Advanced Search mode, then in the results screen, choose the ADVANCED IMAGES tab

Question # 6 (searching by fields)
In simple WEB PAGE SEARCH mode (not advanced) search just with the url field.  How many web pages are found when looking for smcvt in the url?

How many pages with smcvt in the url also include the word library?

Question # 7 -
Choose 2 search engines of your choice found  @ http://www.notess.com/search/features/   or elsewhere.  Note: click on the search engine to access when at this site.

Do identical searches in both search engines.  Compare the results of the two search engines.  Does the size of the search engine as evaluated @ http://searchenginewatch.com/reports/sizes.html explain the difference in results?  What other possible explanations are there for differences in search results and ranking of results @ http://searchenginewatch.com/webmasters/rank.html

ALSO, Evaluate one search engine by the criteria 1-13 at the start of this page: 1. Boolean Searching, 2. Truncation, etc.
use http://www.notess.com/search/features/   or your Textbook (page 145) as an easy comparison guide.

Question # 8
What is your favorite search engine?  Send this to me (url) via email sburks@smcvt.edu   with a short 1 or 2 paragraph description of this search engines virtues.        

Question #10   Using the Argus Clearinghouse @  http://www.clearinghouse.net/    -  find an Internet Guide to a Subject Area you are interested in.   Note how Argus evaluates the guides.  After looking over the guide you have selected, give your opinion on whether Argus evaluated the site "correctly."     Another site to try for Internet Guides is SignPost @  http://www.signpost.org/signpost/