1. Understand the Business Function
ACS 367
Step #2

2. Business Function
Perform business definition and requirements analysis
Determine basic business functions
Describe current activities through task analysis
Develop a conceptual model of the system
Establish design standards or style guides
Establish system usability design goals
Define training and documentation needs

3. business definition and requirements analysis
Establish the need for a system
Determine requirements
Direct Methods
Observational study, prototyping, usability labs
Indirect Methods
MIS intermediary, Surveys…

4. Determining Basic Business Function
A detailed description of what the product will do is prepared.
Major system functions are described (IPO)
A flowchart of major functions is developed

5. Task Analysis
Task analysis involves breaking down user’s activities to the individual task level.
The goal is to obtain an understanding of why and how people currently do the things that will be automated.
Knowing WHY: establishes the work goals
Knowing HOW: provides details of actions performed to accomplish the goals.

6. Task Analysis Task analysis provides information concerning:
Work flows
Interrelationships between people
Objects
Acionts
The output of a task analysis is a complete description of all user tasks and interactions.

7. Task Analysis
A goal of task analysis and a goal of understanding the user, is to gain a picture of the user’s mental model.
A mental model is an internal representation of a person’s current conceptualization and understanding of something.

8. Mental Models Guidelines for designing mental models
Reflect the user’s mental model not the designer’s
Draw analogies or present metaphors
Success of desktop metaphor
Comply with expectancies, habits, routines and stereotypes

9. Design Standards or Style Guides
Value of standards (users)
Faster performance
Fewer errors
Reduced training time
Better satisfaction
Better system acceptance

10. Design Standards or Style Guides
Value of standards (designers)
Increased visibility to HCI
Simplified Design
Reduced redundant effort
Reduced training

11. Design Standards or Style Guides
Document Design
Include many concrete examples of concrete design
Provide rationale describing conditions under which various design alternatives are appropriate
Provide good access
Table of contents
Index
checklists

12. Design Standards or Style Guides
Examples (ISU iGuide)

13. Usability Goals Usability (Bennett, 1979)
The capacity to be used by humans easily and effectively, where
Easily:
to a specified level of subjective assesment
Effectively:
To a specified level of human performance

14. Common Usability Problems
Ambiguous menus and icons
Unclear step sequences
More steps to manage interface that to do tasks.
Inadequate feedback and confirmation

15. Measures of Usability Are people asking a lot of questions?
Are frequent exasperation responses heard?
Are there many irrelevant actions being performed?
Are there many things to ignore?
Do a number of people want to use a product?

16. Criteria for Measuring Usability
Effectiveness
Level of performance
Be specific here (required percentage)
Learnability
Within some specified time (learning curve)
Flexibility
Allowing adaptation to some specified percentage variation in tasks
Attitude
Levels of tiredness, discomfort, frustration…