Transcript HFE 451/651 User and Task Analysis
HFE 451/651 User and Task Analysis
From: User and task analysis for interface design. Hackos & Redish, 1998. New York: John Wiley & Sons.
Topics
Needs Analysis User Analysis Task Analysis Conceptual Evaluation Plan
Needs Analysis
Establish that a system (or product) is needed based on goals of organization and/or marketplace.
Basic goals Purpose features Specify what will be required in the system and what would be “nice to have”.
User Analysis
Understanding the users (examples) Who are the users?
What do the users want?
What are the users goals?
What are individual characteristics that may affect behavior with software or information designed?
What do they know that helps them perform their tasks?
What values to they bring to their job? Do they want a user interface that is fun, not boring?
Understanding the users (cont.)
Are they interested in saving money, saving time, becoming an expert, having an easy job to do?
What is their prior experience with similar tools and interfaces?
What jobs or tasks will the be performing? Under what conditions?
User Analysis
Users you may want to study include: users who buy and use the software alone (e.g. at home) users who use it as part of the work they do groups of people who use software as part of a larger business process software administrators users who repair or troubleshoot users who install customers of the users
User Analysis
Some examples of data to collect Age, gender, physical differences, experience in job, educational level, background of training geographic location, wage differences, culture and nationalities language skills, terminology differences job level (eg. technicians vs engineers, or technicians vs doctors) Assumptions about the users (how to test these assumptions) Mental models users have Individual differences Motivational differences
Task Analysis
Complete description of tasks, subtasks, and methods for performing task.
Analysis of users tasks - what they do and what they need to do.
Function analysis - determining what functions the system as a whole (computer and user) will include Task-Function allocation - What will be allocated to the various components of the system (e.g. what will the user do, what will the system do) Requirements Analysis - What will be the requirements for the design.
Task Analysis
User Goals Relating Goals to tasks and actions Choices of task to meet goals What users do when they encounter problems
Types of Task Analyses
Work Flow Analysis What is the process by which they accomplish the work. This includes work that flows across people.
Where are communication links?
Types of Task Analyses
Job Analysis Understanding what a person does in their particular job. What tasks do they perform?
Frequency: How often do they perform the tasks?
Criticality: How important are the tasks?
Time: How time consuming are the tasks?
Difficulty: How difficult are the tasks?
Division of responsibility: Do all people in the job perform this task?
Techniques for Task Analysis
Task Lists or Inventory Good for pre-design.
What tasks do the user want to accomplish using the product? (Does not tell you how!) Example: Email Program write message send message receive message read message save message etc..
Techniques for Task Analysis
Process analysis or task sequences Series of tasks that users are likely to do (or must do) in a certain order E.g. write a mail message precedes sending it.
Example, operational sequence diagram
Techniques for Task Analysis
Task hierarchies Task can be decomposed into their sub-tasks
Techniques for Task Analysis
Procedural analysis Determine what a user does in performing a specific task. What decisions and actions must be made?
Shows how users are currently using tools.
Consider stages of users
Novices Novices are goal and task oriented Novices do no want to learn, just do Advanced Beginners Focus on accomplishing task Impatient with learning concepts rather than performing tasks Randomly access tasks By adding new and more complex tasks begin to develop empirically based mental model
Consider stages of users
Competent performers Focus on accomplishing more complex tasks that require many coordinated actions Ability to plan how to perform a complex series of tasks to achieve a goal Willingness to learn how the task fits into a consistent mental model of the interface as a whole Interest in solving simple problems by applying a conceptual framework to diagnose and correct errors
Consider stages of users
Experts Focus on developing a comprehensive and consistent mental model of the product Ability to understand complex problems and find solutions Interest in learning about concepts and theories behind a product Interest in interacting with other experts