Home > Database Choices > Curriculum
Cache Advantange
Limiting a search to the past offers some advantages. First, the pages retrieved match the snippet descriptions. Cached Web pages always contain the keywords promised by the snippets. That is not always the case when going from a snippet to a live page. Moreover, the page listed will always be retrieved--no more 'Page Not Found' messages. Another advantage of searching the cached page is that keywords matching the query are highlighted and easier to spot (e.g., BBC example). This can really be a benefit to searchers, including younger students, who are challenged by scanning text to find keywords.
Three ways to search a cache or database
 |
Search Engine -- by far the most efficient and powerful means of finding archived information. Requires the ability to translate a question into a query and select effective keywords and operators. The effectiveness of a search engine is limited by the number of items collected by crawlers and indexed in an associated database. Looking for information that is indexed in a different database than the one being used involves Deep Web searching. There are many search engines, including Google, Yahoo, Ask, JSTOR and the WayBackMachine.
Subject Directory -- an effective means for finding information that has been categorized by editors. Requires browsing and interpreting keyword categories. Limited to a relatively small number of records selected by directory editors and constrained by the keywords they use. A directory may consist of snippets and/or links and represents a fraction of the contents of the complete database. Subject Directories are available at Google, Yahoo and many other sites.
Browsing -- a manual approach to searching that involves scanning text and clicking relevant links found in a subject directory or live Web page. Effective browsing requires experimentation and prediction: being able to select a link that is likely to advance the search in the direction of its objective. Limited only by the user's knowledge of specific URLs to visit and links connecting one page to another.
|
 To learn more about Browsing, check out Live Searching: About Browsing
Lesson Activities: Find the Keywords
(Elementary Grades, Middle School, High School)
Provide students with a series of links to cached pages or queries they can use to find a cached page.
For example,
Here's a link to a cached page on meerkats from Animal Planet.
A query that can be used to find a cached page such as the one above is: site:animal.discovery.com meerkat (it uses a special operator to search only animal.discovery.com for occurrences of meerkat).
Demonstrate to students that the keyword 'meerkat' is highlighted on this page (once in the header and three times in the body of the article on the day this activity was created). They are easy to identify by scrolling down the page.
For younger or more novice students, have them look up these cached pages and find the number of times the keyword appears on the page (links are kept intentionally short since the cached URLs are so long):
| keyword(s) |
cached pages |
live pages |
| Emperor Penguins |
Emperor Penguins |
http://animal.discovery.com/fansites/mostextreme/episode/episode_02.html |
| Hummingbird |
Rufous Hummingbird |
http://animal.discovery.com/guides/wild-birds/i-r/rufous-hummingbird.html |
| Whale |
Whale Songs |
http://animal.discovery.com/news/briefs/20060327/whalesong.html |
| Chicken and Chickens |
Chicken Smarts |
http://animal.discovery.com/news/briefs/20050711/chicken.html |
| Horse and Horses |
Horse Talk |
http://animal.discovery.com/news/briefs/20060612/horsetalk.html |
Speed Search I: For older or more advanced students, divide the group in half (or pairs), giving one half (the "searchers") a link to the cached page and the other half (the "browsers") a link to the live page, making sure ahead of time the pages have identical content. The "browsers" may use any means possible to count the number of keyword matches on the page, including the Find Command. Start with a countdown and see who can come back with the correct number of matching keywords on the page. Switch roles if students want to see how fast they are at searching or browsing. This activity quickly makes the point that using the Cache is by far the fastest way to find the keywords.
Speed Search II: For older or more advanced students, divide the group in three (or groups of three), designating each group or member of each threesome one of the following: "search engine," "subject directory" and "browser." All three groups will attempt to find information to answer the first question:
1 |
 |
What is the URL of a page that provides a list of hotels in Baghdad, Iraq? Sample answer (there is more than one right answer) |
Provide a starting point for each group (copy these links):
Search Engine (google.com) Requires using keywords to locate a relevant page
Subject Directory (directory.google.com) From this page the answer is six clicks away
Browser (http://www.travel-language.com/tl/travel/category/asia/china/travel_guides) From this page, the answer is only three clicks away
Start with a countdown and see which group members can come back the quickest with a correct answer. Switch roles for the remaining two challenges. This activity should demonstrate that it takes less time to find relevant information using a search engine than either of the other means, but good scanning and browsing can get there pretty fast too.
2 |
 |
What is the URL of a recipe for chocolate strawberry pizza? Sample answer (there could be more than one right answer) |
Provide a starting point for each group (copy these links):
Search Engine (google.com) Requires using keywords to locate a relevant page
Subject Directory (directory.google.com) From this page the answer is five clicks away
Browser (http://southernfood.about.com/library/holiday/blvalentine.htm) From this page, the answer is only two clicks away
3 |
 |
What is the URL of a page that describes an annual endurance race to the magnetic North Pole? Sample answer (there could be more than one right answer) |
Provide a starting point for each group (copy these links):
Search Engine (google.com) Requires using keywords to locate a relevant page
Subject Directory (directory.google.com) From this page the answer is five clicks away
Browser (http://elmontsonline.blogspot.com/) From this page, the answer is only two clicks away
Debrief the activity by talking about lessons learned, techniques tried and frustrations encountered related to each method of searching or browsing.
|
