What are the goals of Usability? (3)
Effectiveness, Efficiency and satisfaction
What is a conceptual model?
A high-level description of how a system is organised
What are the goals of evaluation? (3)
Assess the extent of system functionality
Assess the effect on the user
Identify specific problems
What is the ISO definition of usability?
Usability refers to the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of user
What does subjective mean in terms of ID?
subjective refers to opinions and feelings which are personal to each individual
What does objective mean in terms of ID?
Something that can be accurately measured, not an emotion.
What does Usability measure?
Usability measures the quality of a user’s experience when interacting with a product or system.
What happens in a typical user-based evaluation?
Participants are asked to perform a set of tasks with the technology developed.
What is quantitative data?
Data to do with numbers
What is qualitative data?
Data that contains words e.g. interviews and questionnaires.
What are some categories of evaluation? (4)
- Lab controlled studies
- Field/in the wild studies
- Observation methods
- Questionnaires, Interviews, Focus Groups
Where is usability testing typically conducted?
in a laboratory or a natural setting
What methods does Usability testing involve typically? (3)
- User Interviews
- Participatory Design
- User Questionaries
True or False: Some methods can collect both quantitive and qualitative data.
True, for example: Questionnaires can have both ratings-based questions and open-ended questions
What are some considerations of testing methods?
- Reliability
- Validity
- Bias
- Scope
What is the reliability of a method?
Make sure that repeating the experiment will give you similar results
What is the Validity of a method?
The accuracy of a method to measure what it is intended to measure
What is the Bias of a method?
The unintentional influence of the experimenter’s expectations, beliefs or preconceived notions on the outcome of a study or research experiment
What is the Scope of a method?
The boundaries and extent of a study - “This study is designed to investigate x attributes”
What are Questionnaires common for?
Collecting User Feedback
What are the advantages of using a standardised questionnaire?(3)
- It measures exactly what you want it to measure
- Do not have to design the questionnaire yourself (resource-saving)
- You can compare scores across other designs
What are the 3 types of interviews used in Testing and Evaluation>
- Structured
- Semi-structured
- unstructured
What are the Advantages of Interviews? (4)
- Can be varied to suit context
- issues can be explored more fully
- can elicit user views and identify unanticipated problems
- relatively cheap
What are the disadvantages of Interviews? (2)
- Can be subjective
- Time Consuming
