Web Searching

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Web Searching
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Introduction

• The World Changes Constantly
• New Companies
• Products and Product innovations
• Online resources to improve our quality of life

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The Vast Internet

• 2 Billion pages
• Tripled in last two years and growing rapidly

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Web is an Immense Resource

• Research your competitors
• Research gospel topics and do genealogy
• download music, software, drivers
• Product evaluations
• Job searching

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The Good, Bad, and the Ugly

• Gospel Resources Vs. Smut
• Credible Vs. Non-credible

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How the web is indexed

• Search Engines
• Single-Threaded (Spider-based)
• Multi-threaded (Meta) Search Engines
• Subject Indexes

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Characteristics of All Web Indexes

• Limited Samples
• No central, all-inclusive index
• Snapshots
• never completely current
• All indexes miss some content
• You need effective searching strategies

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Varying Samples
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Single-Thread Search Engines

• Powerful Searching Features
• (Match All Terms)
• Match Any Term
• - (exclusion)
• Phrases
• Title Search
• URL Search
• Domain Search

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Multi-threaded (Meta) Search Engines

• Sample Multiple Other Databases in one interface
• Broader sample than single-thread
• Can chose which other single-thread to sample.
• Less options for specific search control
• Cant do URL, Title, and exclusion Searches

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Examples

• Metacrawler (http//www.metacrawler.com)
• Ixquick (http//www.ixquick.com)
• SurfWax  (http//www.surfwax.com
• Dogpile (http//www.dogpile.com)
• ProFusion (http//www.profusion.com)

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Subject Directories (general e.g., yahoo)

• Substantial Sites Organized by Categories (by
  humans)
• Good for searching for general topics
• Yahoo has the largest on the Web with over 1
  million sites listed in their subject directory
• Looksmart is another subject directory used by MSN

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Subject Directory / Crawler-Based Search Engine
Combination

• It is becoming more popular to link subject
  directories with crawler-based search engines
• These look first within subject directory and if
  that fails, they look within a crawler-based
  index
• E.g.1, Yahoos extensive subject directory is
  seached. Yahoo then calls Googles crawler based
  engine
• E.g.2, MSN used the Looksmart subject directory
  then calls on Inktomis crawler based engine.

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Percent of web users using the search engines
each month
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In-Class Examples
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Summary Search Tips

• Use search terms, combination, and phrases.
• Reduce the number of haystacks searched by
  finding a specialized haystack
• Information in a known domain
• Search within a focused directory like Google
  Directory search
• If your index doesnt return results
• Try a different index
• Try a meta search engine