TRAINING PACKAGE
The User Action Framework
Reliability Study
July 1999
What is the UAF?




Conceptual framework of usability concepts and issues
Formed by combining a user interaction cycle with a
knowledge base of usability concepts and issues
UAF provides a basis for: organizing, discussing,
classifying, and reporting usability problems
Is the basis for a set of usability support methods and
tools:
 Usability Problem Design Guide
 Usability Problem Inspector
 Usability Problem Classifier
 Usability Problem Database
The Interaction Cycle




Helps organize usability
issues and concepts
Adapted from Norman (1986)
A picture of how interaction
happens
Based on user actions
(cognitive and physical)
Flow of Interaction Cycle
Planning
 Identify work needs in problem domain
 Establish goals
 Decompose into tasks to be performed on
computer
 Establish intentions (lowest level tasks still
in problem domain terms)
 Translate into plan for physical action, first
mention of action on UI objects
 User physical input
action(s)
 Issues of:
· Fitts' law
· Manual dexterity
· Hand-eye coord.
· Physical disabilities
Physical user action
 Accept and process user
inputs
 Perform non-UI computation
(state change = outcome)
 System response
(representation of outcome)
System action
 Perceive, notice
system response
 Understand system
response
 Evaluate outcome
Assessment of outcome
About Planning

Planning breaks down into two important
parts:
 High-level planning
 Translation
Goal:
Always work/problem domain (e.g., produce
business letter)
Task:
Planning tasks to be done using computer (e.g.,
formatting the page)
Intention:
Action plan:
Planning intentions to be done using computer
(e.g., user intends to set left margin)
Plan for physical actions to be done on computer
(e.g., decide to drag margin marker in MS Word)
About High-Level Planning



Where user decides what to do
Identify work needs and establish goals,
tasks, and intentions
Example areas:
 Goal decomposition (what to do next,
understanding sequence of tasks)
 User’s model of system (understanding
overall system model/metaphor,
expectations)
About Translation



Where user figures out how to do it (“getting
started”)
Translating from the language of the problem
domain to the language of actions upon user
interface objects
Example areas:
 Existence of a way (missing feature)
 Cognitive affordance to show the way
(visual cues)
 Efficient way to “do it” (accommodating
different user classes, shortcuts)
 Help user do right thing (error avoidance)
About Physical Actions


All user inputs to operate controls and
manipulate objects within the user
interface (e.g., clicking, typing, dragging)
Example areas:
 Perceiving affordances
 Manipulating affordances
 Physical control
 Fitts' law
 Manual dexterity
 Physical accessibility and disability
About Outcome



Internal state change within system due to the user action
User normally infers the outcome based on system response,
through feedback
Example areas:
 System automation

Locus of control

System is presumptuous about what the user wanted

System errors
About Assessment



Evaluate what happened and the favorability
or desirability of the outcome
How feedback is perceived, understood, and
used to assess the outcome of a user action
Example areas:
 Existence of feedback (necessary but
missing, unnecessary, not expected)
 Appearance of feedback (legibility,
noticeability)
 How well feedback is expressed (clarity,
completeness, efficient)
Classifying Problems



Finding the correct entry point in the Interaction Cycle for
a usability issue is based on asking:
 How the user and task performance are affected by the
design during interaction
Classification of a usability situation begins by associating
it with the appropriate cognitive or physical user action in
the Interaction Cycle
Then the usability situation is classified within the
taxonomy underneath the Interaction Cycle by
systematically matching usability attributes that pair up
effects of a design feature on the user with usability
problem causes in the interaction design
Cause and Effect

Locate the Cause-in-Design (essence of the problem)
Select one or more Effect-on-User attributes
Example: Hard to read feedback message


Cause-in-Design
Effect-on-User
Slowed down


Assessment
Difficulty with perceiving
Presentation

Perceptual Issues
 Legibility
Key Terms




Cognitive affordance (visual cues to see a button)
 Aids for knowing and understanding
 Aids to show the way
Physical affordance (a button that can be “clicked”)
 Aids for doing
Example
 A chair provides both. Physical affordance of a chair allows
sitting on it. Cognitive affordance of a chair lets user see
that it is something to sit on
Effective affordances support the users' ability to plan
physical actions to carry out intentions