Screen design Week - 7

Emphasis in Human-Computer Interaction Usability in Software Engineering Usability in Software Engineering User Interface User Interface

What is Usability? Learnability Learnability Efficiency Efficiency Satisfaction Satisfaction

Less Effort Reduce time to perform Reduce time to perform Reduce error rate Reduce error rate

Defining the User Interface What the user interface includes What the user interface includes –What user sees, touches, hears, etc. –How the user is allowed to interact with the system –Technologies to facilitate the interaction

Defining the User Interface What the user interface includes (cont.) What the user interface includes (cont.) –Hardware the user sees and touches –Software that permits user to create and modify interface features –Off-line materials, e.g., a manual

Defining the User Interface Components of interaction Components of interaction –Physical acts -- move a mouse, press a key, etc. –Perceptual acts -- recognize an icon, perceive system state, etc. –Cognitive acts -- formulate task goal, decide among menu choices, etc.

The Human Interface as a System Component The embedded interface The embedded interface The interface as a major component The interface as a major component

Reasons for Improving the User Interface Reach larger and new markets. Reach larger and new markets. Make human-computer communication more efficient Make human-computer communication more efficient Raise productivity Raise productivity

What to Consider When Designing the User Interface: Designing for the user Designing for the user Understanding the tasks Understanding the tasks Definition of usability for the current system Definition of usability for the current system Evaluation methodology Evaluation methodology

Necessary Knowledge for Designing the User Interface: Graphical user interfaces Graphical user interfaces Menus Menus Styles of Interaction Styles of Interaction Multimedia Multimedia Screen Design Issues Screen Design Issues

Two Basic Rules for Interface Design Provide a positive initial experience Provide a positive initial experience Be consistent Be consistent

New Media

New Media: Post GUI Interface Beyond 2D Widgets Beyond 2D Widgets Multimodal Multimodal Aesthetic Enrichment Aesthetic Enrichment Multiparticipants: Cultural Sensitivity Multiparticipants: Cultural Sensitivity

New Media Text Text Picture Picture Animation Animation Music Music Narration Narration Video Video Sound Sound Vision Vision Imagery Imagery Hypermedia Hypermedia Voice Voice 3-D Graphics 3-D Graphics 3-D Tactile 3-D Tactile Virtual worlds Virtual worlds

New Media Applications Education Education Reference Reference Communication Communication Services Services Entertainment Entertainment

New Media Interface Issues Enriched Aesthetics Enriched Aesthetics Multimodality Considerations Multimodality Considerations Virtual Worlds Virtual Worlds Social Interaction Social Interaction

Multimedia Concerns in Interface Design Identify purposes for diverse media components Identify purposes for diverse media components Develop, produce, and refine media components Develop, produce, and refine media components Integrate multimedia components into a cohesive system Integrate multimedia components into a cohesive system

For MultiMedia Interface We Need Multiple Expertise Programmers Programmers User Interface Specialist User Interface Specialist Graphic Designer Graphic Designer Video Production Video Production Sound Production Sound Production Technical Writer Technical Writer

Exercises

Exercises

Exercises

Class Exercise Discuss the effects of the audience characteristics on two of the following – focus on the user experience that you would like to design for these users: Discuss the effects of the audience characteristics on two of the following – focus on the user experience that you would like to design for these users: –A multimedia information kiosk for the 2000 Olympic games –A multimedia dietary assessment program for fourth and fifth graders –A genealogy program intended for use by senior citizens –A hypermedia training program for operators at a wastewater treatment plant

Usability Methods Analysis Analysis –Task –Audience Design Design –Storyboards and Scenarios –Prototyping –Metaphors and Conceptual Models Evaluation Evaluation – Experiments – Predictive Methods – Interpretive Methods

Design Methodology for Specifying the User Interface Metaphor UsabilityRequirementsDocument System/definition & Objectives FunctionalRequirements Audience Definition Individual Differences Cognitive Limit User Levels User Types Task Analysis/ work Environment Profile InterfaceMetaphorPlatformSpecifications UsertellDocument Technologies of Interaction Library Usability Testing and Evaluation Plan User Interface & Human Factors Guidelines User’s Task Representation

The User Role in Interface Design Attitude Attitude Experience Experience Information Source Information Source

Defining the Audience Demographic factors Demographic factors Job/Role factors Job/Role factors Task factors Task factors Personal factors Personal factors

Audience Characteristics Education level Education level Education type Education type Readability level Readability level Skill Skill

Audience Characteristics Knowledge Knowledge Experience (type) Experience (type) Experience level (with above types) Experience level (with above types) Tolerance level Tolerance level

Audience Characteristics Cognitive style Cognitive style Learning style Learning style Cultural Cultural Language factors Language factors

Audience Characteristics Individual and demographic attributes Individual and demographic attributes Physical limitations / capabilities Physical limitations / capabilities Task / job related user attributes Task / job related user attributes Affective factors Affective factors

New Media Usability Methods Participatory Methods Participatory Methods Guidelines Guidelines Metaphors and Scenarios Metaphors and Scenarios

Design Methodology for Specifying the User Interface Metaphor UsabilityRequirementsDocument System/definition & Objectives FunctionalRequirements Audience Definition Individual Differences Cognitive Limit User Levels User Types Task Analysis/ work Environment Profile InterfaceMetaphorPlatformSpecifications UsertellDocument Technologies of Interaction Library Usability Testing and Evaluation Plan User Interface & Human Factors Guidelines User’s Task Representation