Chapter 3 : The Problem of Web Navigation

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Chapter 3 The Problem of Web Navigation

• Users often get lost in hyperspace when
• Following links on web pages, or
• Jumping to and from search engine results.
• Machine learning can provide a sound basis for
  improving web intreraction.

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Getting lost in hyperspace

• Figure 3.1 The navigation problem

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Getting lost in hyperspace

• Figure 3.2 Being lost in hyperspace

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The Naïve Bayes ClassifierAutomatic
classification of web pages can widen the scope
and size of web directories
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Trails should be First-Class Objects

• Figure 3.3 Example web site

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Trails should be First-Class Objects

• Figure 3.4 Four trails within a web site

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Trails should be First-Class Objects

• Figure 3.5 Query results for mark research

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Trails should be First-Class Objects

• Figure 3.6 Relevant trail for mark research

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Markov chains

• Markov chains have been extensively studied by
  statisticians and have been applied in a wide
  variety of areas.

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The probabilities of following links

• Figure 3.7 Markov chain for example web site

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The probabilities of following links

• Figure 3.8 Two trails in the Markov chain

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The probabilities of following links

• Figure 3.9 Probabilities of the four trails

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The relevance of links

• Figure 3.10 Scoring web pages

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The relevance of links

• Figure 3.11 Constructing a chain from scores

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Conflict Between Web Site Owner and Visitor

• The web site owner has objectives related to the
  business model of the site, e.g. selling products
  in an e-commerce site.
• The objectives of visitors are related to their
  information needs, e.g. gathering information in
  an e-commerce site.
• Web site owners would like to identify their
  visitors (e.g. via cookies), while visitors may
  prefer to remain anonymous.

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Conflict Between Semantics of Web Site and
Business Model

• E.g. the objective of an e-commerce site is to
  convert visitors into customers.
• But to keep visitors satisfied a web site must
  provide solutions to users information needs.
• There must be a balance between web site
  navigability and the business objectives of the
  site.