Lecture 9 Flashcards
Interaction Design Basics contents?
Design The Design Process Users Scenarios Navigation Iteration and Prototypes
Design?
What it is, interventions, goals, constraints
The Design Process?
What happens when
Users?
Who they are, what they are like?
Scenarios?
Rich stories and design
Navigation?
Finding your way around the system
Iteration and Prototypes?
Never get it right the first time
The process of design steps (Graph)
What is wanted
Analysis
Design
Implement and deploy
The process of design steps? (List)
Requirements Analysis Design Iteration and prototyping Implementation and deployment
HCI in the software process?
Software engineering and the design process for interactive systems
Usability engineering
Iterative design and prototyping
Design rationale
Software Engineering is the?
Discipline for understanding the software design process, or life cycle
Designing for usability?
Occurs at all the stages of the life cycle, not as a single isolated activity
Requirements need?
Clarification, refinement, completion, re-scoping
Why “establish”?
Requirements arise from understanding users’ needs.
Types of requirements?
Functional
Non-Functional
Data
Different context of requirements?
Physical
Social
Organisational
Physical?
Dusty, noisy, vibration, light, heat, humidity?
Social?
Sharing of files, of displays, in paper, across great distances
Organisational?
Hierarchy, IT department’s attitude and remit, user support
Characteristics?
Nationality, educational background
System use?
Novice, expert, casual, frequent
What are the user’s capabilities?
Size of hands Motor abilities Height if designing kiosk Strength Disabilities
Verification vs Validation?
Verification
- Designing the right thing
Validation
- Designing the thing right
The formality gap?
Validation will always rely to some extent on subjective means of proof
Serious Claim?
All of the requirements for an interactive system cannot be determined from the start
The result?
Systems must be built and the interaction with users observed and evaluated in order to determine how to make them more usable
Usability Specification?
Usability attribute/principle
Measuring concept
Measuring method
New level/worst case/planned level
Problems?
Usability specification requires level of detail that may not be possible early in design
Traditional Usability Categories?
Effectiveness - Can you achieve what you want to Efficiency - Can you do it without wasting effort? Satisfaction - Do you enjoy the process
Top 5 Criteria by which measuring method can be determined?
- Time to complete the task
- Per cent of task completed
- Per cent of task completed per unit time
- Ratio of successes to failures
- Per cent or number of errors
The problem with usability metrics is that?
they rely on measurements of very specific user actions in very specific situations
Iterative design?
overcomes inherent problems of incomplete requirements by cycling through several designs, incrementally improving upon the final product with each pass
On the technical side?
Iterative design is described by the use of prototypes - artifacts that simulate or animate some but not all features of the intended system
Management side potential problems?
Time (Building prototypes takes)
Planning (Do managers have experience)
Non-Functional Features (Safety and reliability)
Contracts (Documentation and binding contracts)
What is a Prototype?
Working representation of a final artifact
Prototype dimensions?
Representation (Form of the prototype)
Precision (Level of detail)
Interactivity (Watch-only vs fully interactive)
Expected Life Cycle of Prototype
3 Main approaches to prototyping?
Throw-away
Incremental
Evolutionary
Throw-Away Prototype?
The prototype is built and tested. The design knowledge gained is used to build the final product. The actual prototype is discarded.
Incremental Prototype?
The final product is built as a separate components, one at a time.
The final product is then released as a series of products, each subsequent release including one more component.
Evolutionary Prototype?
The prototype is not discarded and serves as the basis for the next iteration of design.
Fidelity refers to the?
Level of detail
High Fidelity?
Prototypes look like the final product
Low Fidelity?
Artists renditions with many details missing
Why use Low-Fi Prototypes?
Traditional methods take too long
Can instead simulate the prototype
Kindergarten building skills
Advantages of Low-Fi Prototypes?
Takes only a few hours
Can test multiple alternatives
Almost all interaction can be faked
Disadvantages of Low-Fi Prototypes?
Computer inherently buggy Slow compared to real app Hard to implement some functionality Won't look like the final product End-users can't use by themselves
Some of UI Prototyping Tools?
Outpost Denim Suede Topiary SketchWizard
Why use Prototyping Tools?
Allows brainstorming
Incomplete designs
Adds advantages of electronic tools:
- Evolve easily
- Support for “design memory”
- Transition to other electronic tools
- Allow end-user interaction
Techniques for prototyping?
Storyboards
- Need not be computer based
- Can be animated
Limited functionality simulations
Constructing the Model?
Set a deadline
Draw a window frame on large paper
Put different screen regions on cards
Pitfalls of Prototyping?
- Need a good start point
2. Need to understand what is wrong
Warning about iterative design?
Design inertia - early bad decisions stay bad
Diagnosing real usability problems in prototypes is hard
Design rationale is?
Information that explains why a system/application is the way it is.
Benefits of design rationale?
- Communication through life cycle
- Reuse of design knowledge across products
- Enforces design principle
- Presents arguments for design trade-offs
Types of Design Rationale?
Process Oriented
Structure Oriented
Process Oriented?
Preserves order of deliberation and decision making
Structure-Oriented?
Emphasized post hoc structuring of considered design alternatives
IBIS?
Issue-based information system.
Basis for much of design rationale research Process-oriented Main elements: - Issues - Positions - Arguments
QOC?
Questions
Options
Criteria
