1. Introduction Flashcards
What is usability?
- The user can do what he or she wants to do the way he or she expects to be able to do it, without hindrance, hesitation or questions.
- “Absence of frustration”
- “usability is only an issue when it’s absent”
Of what does usability exist?
- Effectiveness (task completion)
- Efficiency (time spend)
- Satisfaction (no discomfort, positive attitude)
Of what does Bailey’s human performance model exist?
- Somebody (Human)
- Something (activity)
- Some Place (context)
What are the phases of user experience?
- System reliability phase (before 1950s)
- System performance phase (1950’s-1960s)
- User performance phase (1960s-1970s)
- Usability phase (1980s-2000s)
- User experience phase (2000s-)
What is user experience?
“ A person’s perceptions and responses resulting from the use and/or anticipated use of a product, system or service”
What are two ways to look at usability & UX?
- Usability is a part of UX
- UX Is an extension of the ‘satisfaction’ part of usability
What are the stages in the UX in time model?
- Anticipated UX
- Momentary UX
- Episodic UX
- Cumulative UX
What is the when and how of anticipated UX?
- When: before usage
- How: Imagining experience
What is the when and how of momentary UX?
- When: During usage
- How: experiencing
What is the when and how of Episodic UX?
- When: after usage
- How: reflecting on an experience
What is the when and how of Cumulative UX?
- When: over time
- How: Recollecting multiple periods of use
What is usefulness?
“..The degree to which a product enables a user to achieve his or her goals, and is an assessment of the user’s willingness to use the product at all”
What is the danger of early usability testing?
- Fixing problems instead of expanding solution space
Why would you evaluate?
- Inform design decisions (= answer questions)
- Identify and fix design problems
- Money (cost reduction, profit gains)
- Create a sense of involvement
- Generation of scientific / intermediate level knowledge –> generalize
On what should you focus your investigation?
- Behavior “the what”
- Attitude “the why”
What are advantages of informal evaluations?
- Fast & cheap
- Less planning
- Loose recruitment (e.g., even colleagues)
- Less structured (e.g., talk about existing usability issues)
- Less formal output (report)
What should you consider when evaluating?
- Planning (approach, methods, time)
- Sample (Sampling technique, kind of users, size)
- Ethics (Consent, data transparency, privacy)
What is purposive sampling?
recruiting people with one or more special characteristics
What are the three different studies for sample size on evaluation?
Sample size depends on the evaluation.
- Summative/assessment study, emphasis quantitative: 5-7
- Formative/exploratory study, emphasis qualitative: 10-20
- Comparison study: ~30 per group/product
What are different parts of ethics you should keep in mind?
- Informed consent
- Right to withdraw
- Permission to record
- Privacy & confidentiality
- Valid & reliable data
What is intermediate level knowledge?
Research Design
Knowledge Artifacts
What are four potential research directions?
- A more holistic vision for UX Evaluation
- Pragmatic and hedonic - Inspection methods for hedonic attributes
- Psychophysiology - Core skills needed fore evaluation
- What do we all need as an interdisciplinary field? - Learn from evaluation in practice
What is triangulation?
an approach to data collection and analysis
That uses multiple methods, measures, or
Approaches to look for convergence on
Product requirements or problem areas.
What are benefits of triangulation?
- More in depth understanding (how + Why)
- More richness, varied set of data
- More convincing, persuasive recommendations
- Reduce “inappropriate certainty” that not much is wrong with a design
- Prioritizing requirements
