User Centered Design Lecture 7

Study Notes

Sequence includes Task and User Analysis, Design Sketches, Paper Prototyping, User Testing, Computer Prototyping, Heuristic Evaluation, Full Implementation, and final User Testing.

Focus on identifying target user characteristics: age, gender, culture, language, education, physical limitations, computer experience, motivation, and domain/application experience.
Critical to understand user demographics, as assumptions about users can lead to design failures.
Multiple user classes exist, defined by roles (e.g., student, teacher) or characteristics (e.g., age groups, motivation levels).
Methods for analysis include representative user interviews, questionnaires for basic data, and direct observation in natural settings.

Tasks are expressed as goals, focusing on what needs to be accomplished rather than how.
Hierarchical decomposition helps break down a top-level task into subtasks and subgoals.
Hierarchical Task Analysis (HTA) utilizes tree diagrams to illustrate tasks and subtasks, enhancing understanding of user interactions at different abstraction levels.
Benefits of HTA include objective comparisons of task approaches regarding step numbers and types, facilitating effective UI design.

Each task must include the following elements:
- Goal: The task's name.
- Preconditions: Necessary conditions that must be met before attempting the task.
- Subtasks: Detailed steps involved in completing the task.

Goal: Purchase a sweatshirt.
Preconditions: Knowledge of desired product type and chosen payment method.
Subtasks: Selecting the product, confirming the purchase, updating information, and final payment confirmation.

Aims to identify important elements within a domain and their interrelations.
Domain entities include people (user classes), physical objects, and information objects (e.g., purchase orders, emails).
Represent entities as labeled boxes and illustrate relationships with edges:
- "has-a" relationship indicates ownership (e.g., a customer has an account).
- "is-a" relationship signifies subclassing (e.g., teachers and TAs are both instructors).

Key entities identified are Sysadmin, Users, Accounts, Products, and Messages.
Relationships establish interactions, such as users creating accounts and buying products.
Multiplicity denotes the quantity of relationships (e.g., ! for exactly one, ? for zero or one, + for one or more, * for zero or more).

Incorporates insights from user, task, and domain analyses into the broader requirements analysis process, ensuring comprehensive understanding and addressing of user needs.