Transcript How do Search Engines Work?

Matakuliah
Tahun
Versi
: M0284/Teknologi & Infrastruktur E-Business
: 2005
: <<versi/revisi>>
Pertemuan 19
Searching Mechanisms
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Learning Objectives
• Describe the role of search engines in ebusiness
• Explain how search engines work
• Describe use of search engines in intranet and
extranet environment
• Identify important search engines in the market
• Describe a flexible search strategy
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Overview
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Need for search engines
History of search engines
How do search engines work?
Common search features
Common display features
Subject directories and specialized
databases
• Meta-search engines
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Overview (Cont’d)
• Evaluation of search engines
• Search engines listings
• Popular search engines
• A flexible Search Strategy
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Need for Search Engines
• E-Commerce
– Microsoft, Oracle web sites over 1 million pages
• Multi-media databases
• E-Governance
– business, citizens: rules, regulations
• E-Employee
– rules, regulations, human resources
• E-Business
– product specifications, catalogs, contract details,
availability
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History of Search Engines
• Anonymous FTP sites
• Archie
– for searching FTP sites
• Gopher servers
– for text documents
• Veronica
– for searching Gopher sites
• Spiders
– to collect and search URLs, titles and web headings
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How do Search Engines Work?
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How do Search Engines Work?
• Gathering
– visit web sites, bring document copies
• Indexing
– collect key words, phrases and index against
URLs
– Spider server
• Searching
– search index of words/ phrases
– Index server
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How do Search Engines Work?
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Common Search Features
• Boolean Searching
AND
OR
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Common Search Features
• Phrase Search
• Proximity Search
“acid rain”
America NEAR warming
• Wild card Search
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• Concept Search
• Natural Language Search
?
Ask Jeeves
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Common Display Features
• Relevance Ranking
• How to arrange the output of the search engine?
– Frequency
– Popularity of the site
– Location of the words
– Connectivity of the page and site
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