What about Chapter 7?

What is the usability process? Tyldesley’s 22 possible Measurement Criteria Let’s focus on usability–A usability initiative needs usability goal(s). In Web C, what were the Evaluation Objectives? Our author defines usability requirements as: The desired qualitative or quantitative usability goals for a system 1. Time to complete task. 2. Percentage of task completed 3. Percentage of task completed per unit time (speed metric. 4. Ratio of successes to failures. 5. Time spent on errors. 6. Percentage or number of errors. 7. Percentage or number of competitors that do this better than current product. 8. Etc. What are these? UIDE Chapter 6

 Learnability – time and effort required to reach a specified level of use performance  Throughput – tasks accomplished by experienced users, speed, and errors  Flexibility – extent to which system can accommodate changes  Attitude – positive attitude of users UIDE Chapter 6

The Modern-Day View of Usability ◦ 5 E’s  Effective  Efficient  Engaging  Error tolerant  Easy to learn Constraints and Trade-offs in Relation to Requirements Gathering ◦ Costs/Budgets/Timescales ◦ Technical Constraints ◦ Trade-Offs What is the cost of a defect in requirements? UIDE Chapter 6

 Requirements Specification ◦ User characteristics ◦ Tasks and task characteristics ◦ Environmental factors ◦ Usability ◦ Constraints and trade-offs UIDE Chapter 6

◦ Purposes of Prototyping: Why Bother Trying Out Your Ideas?  Check feasibility of ideas with users  Check usefulness of the application  Allow users to contribute  Allow users to test ideas  Validate requirements  Negotiate requirements UIDE Chapter 6

◦ Low-Fidelity Prototypes  Sketching  Screen Mockups  Storyboards UIDE Chapter 6

 High-Fidelity Prototypes: Using Software Tools to Try Out Your Ideas  Cautions about Prototyping UIDE Chapter 6

 Creating the physical Design of the user interface (UI)  Issue of work reengineering ◦ Power ◦ Efficiency ◦ Effective support of business goals UIDE Chapter 8 User needs and requirements

 Book Example in Ch. 8.1 ◦ Introduction to the Digital Library ◦ Work Reengineering for the Digital Library ◦ Task Allocation for the Digital Library  Graphical User Interface (GUI) Project ◦ Introduction to your idea about organization of your “computing devices” ◦ Web E the pitching of ideas for a new interactive graphical user interface. UIDE Chapter 8

 Part 1 – Usability ◦ Usability Attributes for system development ◦ User Interface Matters ◦ Costs related to poor UI  Part 2 – Requirements ◦ How to gather requirements and create user stories ◦ True Users – Persona – User’s Domains ◦ Describing Users’ Work  Part 3 – Design ◦ Conceptual Design ◦ Choosing for the user’s best devices, interaction, etc. UIDE Chapter 8

 A University department has ◦ Users: _________ __________ _________________ ◦ Tasks: ____________________________ ◦ Individuals have personal libraries to share  Business Motivation for New Digital Library ◦ _______________________ ◦ Track personal resources. UIDE Chapter 8

 Work differently if to work effectively  Goals: ◦ Power and efficiency that automation makes possible ◦ More effectively support business goals ◦ Minimize retraining  To Begin DO:  Task Scenario: represents the present situation.  Use Scenario: description of the anticipated use of the new UI. UIDE Chapter 8

Create a user’s task with setting for an evaluation from these.

UIDE Chapter 8

 Sharing the different “essential” tasks between the user and the computer.  Essential use case: ◦ Index card with User’s Purpose - System Responsibility UIDE Chapter 8 Fig 8.3

 The process of establishing the underlying organization and structure of a UI Content diagram – low fidelity prototype that represents the organization and structure of the user interface from the designer’s perspective. UIDE Chapter 8 Fig 8.5

 Design needs: ◦ Derived concrete use cases ◦ Identify primary task objects, attributes, actions ◦ Identify the containers and the task objects in each one ◦ Link containers to s ◦ how navigation flow. UIDE Chapter 8

 Deriving from Essential Use case. UIDE Chapter 8 Fig 8.6

 Conceptual Design ◦ Deriving Concrete Use Cases from Essential Use Cases ◦ Identifying Task Objects, Attributes, and Actions  Task Objects  Attributes  Actions UIDE Chapter 8

 Task Objects: units of information or data with which the users interact to carry out their tasks. ◦ Includes Class objects, i.e. media types, members of the library  Task Attributes: task object components ◦ Properties and Child Objects  Title and author are properties of book  Owner of CD-ROM is child object of CD-ROM because Owner has its own properties  Task Actions: actions performed on task objects ◦ Allocating guests to rooms. (Add) ◦ Create, delete, copy, save, edit, etc. UIDE Chapter 8

 Task objects – single underline  Attributes of objects – double underline UIDE Chapter 8 Fig 8.8

UIDE Chapter 8 Fig 8.9  Prototyping Task Objects, Attributes, and Actions

UIDE Chapter 8 Use of “Sticky Notes to prototype task objects, attributes, and actions. Fig 8.10

UIDE Chapter 8 Template for Containers Fig 8.11

UIDE Chapter 8 Double Link Fig 8.12

 Main Container UIDE Chapter 8 Fig 8.13

UIDE Chapter 8 Fig 8.14

 Template for Containers  The Main Container  Other Containers  Links  Prototyping Containers and Links  Final Thoughts on Conceptual Design UIDE Chapter 8