Week 4 - Users, Usability and User Experience Flashcards
(25 cards)
Why do different types of users need to be considered
- Not everyone has the same capabilities or understanding of systems or how to use them.
- Many people have different abilities and needs so cannot assume that everyone is the same.
Examples of user centred designs
- Interaction design: Creating intuitive and engaging user interfaces.
- Human-Computer Interaction (HCI): Studying how users interact with computers to improve usability.
- User Experience (UX) design: Enhancing overall user satisfaction and ease of use.
- Requirements engineering: Including usability and security when defining system functions and qualities (requirements).
What aspects of users need to be considered
- Physiological aspects: senses, movement, strength, fatigue.
- Cognitive aspects: attention, memory, learning, cognitive load.
- Affective aspects: emotional responses e.g., engagement, frustration.
Also need to consider how individual users abilities vary and how they change over time.
Limitations to understanding users
- Humans are complex - cannot always fully understand every need/behaviour.
- Differences between users.
- Difficulty in articulating needs.
- Difference between what users say they need and what they actually need.
Scenarios
A method for considering user needs by creating a story representing how a user will interact with a system.
Personas
Character portraits in a scenario that represent typical users based of real data.
Helps designers understand different types of users.
Usability
- A measure of how easy and effective a product or system is to use and how well it meets the needs of its users.
- Can be measured by the effectiveness, efficiency and satisfaction of a system in a specific context of use.
Nielsen’s model of system acceptability
- System acceptability relies on social and practical factors, with usefulness (utility and usability) being a key driver of whether a system is considered acceptable by its users.
- System should be easy to learn, efficient to use, easy to remember how to use, have a low error rate and be satisfying to use.
Approaches to evaluating usability
- Analytical approaches: assessing a system using guidelines or heuristics - expert evaluation.
- Empirical approaches: observations, surveys etc. - user evaluation.
Inspection methods (evaluating usability)
- Heuristic evaluation: experts check against usability principles.
- Walkthroughs: experts simulate user interactions.
- Standards/guideline checklists: review compliance with standards/guidelines.
Inquiry methods (evaluating usability)
- Observations: watch users interact with the system.
- Interviews/ focus groups: gather feedback through discussions.
- Questionnaires: Collect structured user feedback.
Testing methods (evaluating usability)
- Usability testing: Users complete tasks while being observed to identify issues.
Heuristics
- A practical approach to problem-solving using guidelines, shortcuts or rules of thumb.
- Aims for a good enough solution rather than a perfect one.
Nielsen’s usability heuristics
- Simple and natural dialogue.
- Speak the users’ language.
- Minimise memory load.
- Consistency.
- Feedback.
- Clearly marked exits.
- Shortcuts.
- Good error messages.
- Prevent errors.
- Help and documentation.
Pros and cons of heuristic evaluation
+ Quick and inexpensive - fast feedback without needing large groups.
+ Fewer ethical/logistical concerns - no recruitment, privacy/consent handling.
- Requires expertise who can be hard to find.
- Can miss bigger issues.
System usability scale (SUS)
- 10 statements which users rate their agreement on. Gets quantitative feedback.
- Often 1-10 where 1 is “I needed to learn a lot of things before I could get going with the system” and 10 is “I would like to use the system frequently”.
- Often used after heuristic evaluations.
Usability testing
Users are assigned tasks to simulate use of the system then performance measures like time to complete tasks, error rate and success rate are tracked to assess system usability.
Often used after system usability scale evaluation.
Usability metrics
- Key measurements used to evaluate system usability.
Focusses on how well and efficiently users can complete tasks. - Effectiveness is measured by percentage of tasks successfully completed.
- Efficiency is measured by the time taken to complete tasks.
Usability vs user experience
User experience (UX) focuses on how a system feels to the user whereas usability measures how efficient and effective a system is for a user.
User experience is the subjective experience, usability is the practical functionality.
What should be considered when designing a good user experience.
- What: Determine what activities the system allows users to perform.
- How: Design the interaction - how users achieve goals.
- Why: Understand users needs, emotions and motivations.
Dark pattern
Deceptive UI design features that mislead users into making choices not in their best interest.
Exploits people to benefit the service provider and results in users making actions they did not want to.
E.g., concealing key info, using misleading wording, setting defaults that favour the service provider etc.
Roach motel (dark patterns)
A dark pattern where it is very easy for a user to enter a situation but very hard to get out of.
E.g., confusing/complex steps to unsubscribe from a service but straight forward to subscribe.
Forced continuity (dark patterns)
A dark pattern users are required to provide their credit card information to sign up for a free trial.
Users are automatically billed without notice once the free trial ends.
Bait and switch (dark patterns)
A dark pattern where users intend to complete one action, but an undesirable action occurs instead.
E.g., higher price after clicking on a product.
