Advanced Internet Searching Advanced Internet Searching TechniquesTechniques

Internet Search ToolsInternet Search ToolsDifferent types and how to use them.Different types and how to use them.

The web offers the choice of dozens of different search tools, each with it’s own database,

command language, search capabilities, and method of displaying results.

Types of Search ToolsTypes of Search Tools

The most commonly used search tools are Search Engines Subject Directories

Other search tools include Targeted directories Focused Crawlers Portals Vortals Meta-tools Value-added search services

Search EnginesSearch Engines

Search tool most often used. Finds web pages by using small, automated

computer programs called spiders or crawlers. Advantage – Sites are recorded and updated

automatically so the database is HUGE. Disadvantage – Search engines do not evaluate

the web sites for content or accuracy.

Search EnginesSearch Engines

Search engines are the preferred tool when you:

Are looking for something very specific Need to pin down a quick fact or two Need to know if any information exists at all on a

subject Want mass quantities of links, but are not concerned

about quality control.

Examples – Search EnginesExamples – Search Engines

Google – www.google.com Altavista- www.altavista.com Lycos- www.lycos.com Yahoo! Search – http://search.yahoo.com Excite – www.excite.com Alltheweb – www.alltheweb.com

Search EnginesSearch Engines

Natural language search engines allow uses to submit search terms in English rather than using operators, quotes, +signs and other search terminology.

They evaluate proximity of terms, phrase recognition, capitalization and keyword occurrence in titles, subheads and text.

Lexxe – http://www.lexxe.com Hakia – http://www.hakia.com Powerset – http://www.powerset.com

Subject DirectoriesSubject Directories A subject directory is a database of titles,

citations, and websites organized by category. Advantage – Most directories are edited,

maintained and created by people. Usually they are carefully evaluated and annotated for this

reason.

Disadvantage – Typically include a smaller number of sites than a search engine due to the great amount of human effort involved.

Examples – Subject DirectoriesExamples – Subject Directories

Open Directory Project - The largest, most comprehensive human-edited directory of the Web. It is constructed and maintained by a vast, global community of volunteer editors.

Closed model directories such as Yahoo! And LookSmart are pulled together by professional editors who select the links and set up the categories. The user generally gets high quality results

Subject DirectoriesSubject Directories

Subject directories are organized and selective.

They are useful when you want to know more about broad-based subjects, such as

General topics Popular topics Targeted directories Current events Product information

HybridsHybrids

Many search engines are now hybrids- search tools that have an engine as well as a directory.

Sometimes targeted directories are matched with focused crawlers to produce a very powerful hybrid search tool. (e.g. http://www.FirstGov.gov

Metasearch EnginesMetasearch Engines

Metasearches use multiple engines to look for your keywords.

Advantage – You have many search engines all looking for what you need. Great when you are looking for something that is hard to find.

Disadvantage – It’s hard to fine tune your search and narrow things down. Also, Metasearches can sometimes give you more information than what you need.

Examples - MetasearchesExamples - Metasearches

Beaucoup! – www.beaucoup.com Clusty – http://clusty.com Mamma, “the mother of all search

engines”- www.mamma.com Ixquick – www.ixquick.com

Special Search toolsSpecial Search tools

Yahooligans – Made for ages 7-12, pages are hand picked to be appropriate for children. Not only will the content on these pages be monitored, but so are the ads that are displayed.

Froogle – Made for the frugal shopper, this offshoot of Google has engines that catalog products and finds you the cheapest price for a given item on the internet. It’s in it’s “beta” version so they are still working out some kinks.

How Search Engines WorkHow Search Engines Work

inserting the phrase - cat dog -, will result in pages that have:

The word cat in the document

The word dog in the document

The word cat and dog in the document .

Fine Tuning Your SearchFine Tuning Your Search

Boolean LanguageBoolean Language

Boolean - A language that was created to interface with search engines on the internet to help narrow your search.

Uses AND, OR, and NOT (must be in caps.)

Example: “Clinton NOT Lewinsky” on Yahoo!

Math to the Rescue!Math to the Rescue!

Power searching also uses math, the universal language.

Uses symbols of + and – and “”. Example: “Clinton – Lewinsky” on Yahoo!

GoogleGoogle

Find pages containing the term in the title:intitle:[search term]

Find pages with terms in the text:allintext:[search terms]

Find similar pages to a certain website:related:[insert URL]

Find pages with the term in the URL:inurl:[insert search term]

Try it out!

All The WebAll The Web

Find pages containing the term in the title:

title:[search term]

Find pages with the term in the URL:

url.all:[search term]

Invisible WebInvisible Web

Also called “deep web” consists of materials search engines will not or cannot index.

Usually consists of web-based databases or pdf files.

Example: American Memory Project: Jackie Robinson.

Invisible Web Resources Invisible Web Resources

Google – The only traditional search engine that can recognize .pdf and .doc files.

Profusion – a Metasearch tool that lets you search .pdf files.

Search TipsSearch Tips

Step 1 – define the data you want Step 2 – figure out where it’s likely to be

found Step 3 – select the search tool most likely

to provide it Step 4 – learn how to interpret your results