Usability Usability Engineering User-Centred Design

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UsabilityUsability EngineeringUser-Centred
Design

• Computer-Mediated Communication
• Hoorcollege 6 di. 12 okt. 2004

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Shackel over Usability

• A usable product is one that users find
  satisfactory for the tasks for which it was
  designed.
• Good design for usability depends upon achieving
  successful harmony in the dynamic interplay
  between user, task, system, and environment.
• Usability 4 bruikbare criteria
• Learnability
• Effectiveness
• Attitude
• Flexibility

3
ISO over Usability

• Usability is the effectiveness, efficiency and
  satisfaction with which specified users can
  achieve specified goals in particular
  environments.
• Effectiveness accuracy and completeness with
  which users achieve specific goals
• Efficiency accuracy and completeness of goals
  in relation to resources expended
• Satisfaction comfort and acceptability of the
  system

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Dix en Nielsen over Usability

• Model van Dix
• Learnability
• Flexibility
• Robustness

• Nielsen
• (Website Usability)
• Learnability
• Efficiency
• Memorability
• Errors
• Satisfaction

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International Standards HCI/Usability

• Nigel Bevan (2001)
• Type standaarden
• Gebruik in context
• Gebruikersinterface en interactie
• Gebruikers-georiënteerd ontwikkelingsproces
• UCD-bekwaamheid van organisatie

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Software Engineering en Usability

• the capability of the software product to be
  understood, learned, used and attractive to the
  user, when used under specific conditions

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User Interface Standards

• Nadelen
• Beperken ontwerp
• Stagneren vernieuwing
• Beschrijven principes, geen bruikbare oplossingen
• Zijn snel verouderd
• Voordelen
• Leggen good practice vast
• Beïnvloeden houdingen t.a.v. software
  development

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User-Centred Design

• Karat (1996) UCD Quality or Quackery?
• UCD is an iterative process whose goal is the
  development of usable systems, achieved through
  involvement of potential users of a system in
  system design
• I suggest we consider UCD a nice fluffy little
  catch phrase. It captures a commitment that the
  usability community supports that you must
  involve users in system design while leaving
  fairly open how this is accomplished

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15 jaar Usability

• Doelen
• Begrijpen wat de gebruiker nodig heeft
• Voorspellen hoe bruikbaar een software-product is
• Technieken
• participatory design
• user testing
• Analyses
• Heuristic evaluation
• Cognitive walkthrough
• GOMS

• 4 manieren van evalueren
• Automatisch
• Empirisch
• Formeel
• Informeel