Module 2

• Usability testing


  Representative users attempting representative tasks in representative environments, on early prototypes or working versions of computer interfaces
• Interfaces being usability tested

  • Screen layouts for desktop, laptop, tablet computers, smartphones and other mobile devices
  • Physical interaction with devices
• Mobile devices frequently need usability testing due to newer interaction approaches, more content in smaller screen size, and easy accidental activation of features
• Goal of usability testing

  To improve the quality of an interface by finding flaws and areas needing improvement
• Usability testing


  Can be considered a close cousin of traditional research methods, often known as "user research"
• Usability testing


  An industrial approach to improving user interfaces, with less concern for using only one research method or having strict controls
• Types of usability testing/inspections

  • Expert-based tests
  • Automated usability tests
• Expert-based tests


  Structured inspections by interface experts, not the interface developers
• Automated usability tests


  Software applications that inspect interfaces to assess usability, using a set of interface guidelines
• Usability testing can take place anywhere - fixed lab, workplace, user's home, over phone or web
• Task lists


  Used to ensure users are goal-directed, tasks need to be clear and unambiguous
• Metrics utilized in usability testing include measurement of task performance and time performance, similar to experimental design.
• Methods utilized as part of usability testing include surveys to measure user satisfaction.
• Formative Testing - tends to be exploratory and to test early design concepts.

  Formative Testing - include wireframes or paper prototypes, also known as low-fidelity prototypes (Dumas and Fox, 2007).

  Formative Testing - This type of usability testing is often more informal, with more communication between test moderators and participants (Rubin and Chisnell, 2008).
• Summative Testing - Usability testing that takes place when there is a more formal prototype ready, when high-level design choices have already been made, is known as a summative test.

  Summative Testing - The goal is to evaluate the effectiveness of specific design choices. These mostly functional prototypes are also known as high-fidelity prototypes (Dumas and Fox, 2007).
• Validation Test - a usability test sometimes takes place right before an interface is released to the general user population.
• • Task performance or correctness - means how many tasks were correctly completed (and the related metrics of how many tasks were attempted but not successfully completed).

  • Time performance - means how long each task took to successfully complete (and the related metrics of how long people spent on incorrect tasks before they gave up).

  • User satisfaction - is often measured by a standardized, validated survey tool
• Checklists may or may not always help improve your usabilitity tasting