Principles to Support Usability - Robustness

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Principles to Support Usability - Robustness

• Group 3
• Topic 2
• IM2044
• Usability Engineering

Student ID 0422902 0409543
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What is it?

• The level of support provided the user in
  determining successful achievement and assessment
  of goal directed behavior.
• How easy is it to evaluate whether the goals have
  been achieved?

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4 Main principles are Observability

• Browsability defaults reachability
  persistence Operation visibility
• Ability of user to evaluate the internal state of
  the system from its perceivable representation

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4 Main principles are Recoverability

• Reachability forward/backward recovery
  Commensurate effort
• Ability of user to take corrective action once an
  error has been recognized

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4 Main principles are Responsiveness

• Stability
• How the user perceives the rate of communication
  with the system

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4 Main principles are Task conformance

• Task completeness task adequacy
• Degree to which system services support all of
  the user's tasks

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Examples using an Internet browser

• Netscape

Defaults File saves
Persistent Alerts
Reachability Navigation