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’

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

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

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

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

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

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.

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

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

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

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

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.