1. The Design Document References:
Developing User Interfaces: Ensuring Usability Through Product & Process
by Deborah Hix and H. Rex Hartson
© and published by John Wiley & Sons, Inc.
Section 5.2 ‘Design’ (pp. 132 – 144)
The Usability Engineering Lifecycle: A Practitioner's Handbook for User Interface Design
by Deborah J. Mayhew
© and published by Morgan Kaufmann Publishers, Inc. 1999
Chapters 8 and 9 ‘Conceptual Model Design’ and ‘Conceptual Model Mock-ups’
Human-Computer Interaction (Second edition)
by Alan Dix, Janet Findlay, Gregory Abowd, and Russell Beale
© Pearson Education Limited, Published by Prentice-Hall Europe
Section 4.3 ‘Principles to support usability’ (pp. 162 – 177)
Usability Engineering
by Jakob Nielsen
© 1993 Academic Press, Published by Morgan Kaufmann Publishers, Inc.
Chapter 5 ‘Usability Heuristics’

2. Design as Part of UE SE/UE lifecycle is divided into
Definitional activities
e.g. user analysis, task analysis
Development/Design Activities
e.g. design of interaction
UE = usability engineering
This slide is copied from the early analysis activities slides

3. Readings
In Preece et al.
Sections 21.3 – 21.5
Chapters 22 & 23

4. What Is Design? Design is discussed a lot There are many ways to do it
Many practitioners agree on two stages ...

5. Two-stage Design Documents
Stage 1: conceptual design
Synthesizing objects and operations
Stage 2: concrete design
Generate design ideas in a way that can be communicated with the team & users

6. Stage 1: Conceptual Design
Synthesizing objects and operations
The what and how of the users’ tasks
Objects come directly from the users’ tasks
e.g. Articles, words/phrases, passages, sections
e.g. Tracks, albums, lengths
Operations are method the users use to do tasks
e.g. Open/read, close/write, modify, use, delete

7. Stage 1: Conceptual Design
Ask yourself:
What will the user work with?
How will they access and use the objects?
Operations are often about how a user can get to use instances of an object.

8. Questions to Answer in Stage 1 About Objects
What objects to use
What are their properties
How will they be represented conceptually
How will users get access to the objects
A familiar metaphor can help
But don't put too much faith in metaphors
Objects are things  nouns
Operations are actions  verbs
Properties distinguish one object of type x from other object of the same type  adjectives

9. Questions to Answer in Stage 1 About Operations
What are the necessary operations
How will users select those operations (through your system)
How will users perform those operations

10. Stage 2: Concrete Design What Is It?
Put your design ideas in a concrete form
Used to communicate with your team
Used to communicate with users
Write them down or draw/sketch them
Don’t try to make them perfect

11. Stage 2: Concrete Design Why Do It?
Remember: Iteration through the star life-cycle is key
Concrete representations help us to ask basic questions about the interface
see the heuristics and guidelines in
Dix et al.’s Human-Computer Interaction
Nielsen’s Usability Engineering
Norman’s Psychology of Everyday Things

12. What Do I Expect? Turn-in on 26 June (Wed.) At least five pages
Two-stage design document
(Stage one could be done in 1½ hours)
Sketches for some elements would help
Evidence that you have considered the implications of your design & used your (modified) task analysis
Be sure to turn in (revised) HTA with the DD.