Page 100 -

References 69

Key points
It is important to have a good understanding of the problem space, specifying what it is
you are doing, why and how it will support users in the way intended.
A fundamental aspect of interaction design is to develop a conceptual model.
There are various kinds of conceptual models that are categorized according to the activ-
ity or object they are based on.
Interaction modes (e.g., conversing, instructing) provide a structure for thinking about
which conceptual model to develop.
Interaction styles (e.g., menus, form fill-ins) are specific kinds of interfaces that should be
decided upon after the conceptual model has been chosen.
Decisions about conceptual design also should be made before commencing any physical
design (e.g., designing an icon).
Interface metaphors are commonly used as part of a conceptual model.
Many interactive systems are based on a hybrid conceptual model. Such models can pro-
vide more flexibility, but this can make them harder to learn.
3D realism is not necessarily better than 2D or other forms of representation when in-
stantiating a conceptual model: what is most effective depends on the users' activities
when interacting with a system.
General interaction paradigms, like WIMP and ubiquitous computing, provide a particu-
lar way of thinking about how to design a conceptual model.

Further reading

LAUREL, B. (1990) (ed.) The Art of Human Computer De- LANIER, J. (1995) Agents of alienation, ACM Interactions,
sign has a number of papers on conceptual models and inter- 2(3), 66-72. The Art of Human Computer Design also pro-
face metaphors. TW~ that are definitely worth reading are: vides several thought-provoking articles, including one
Tom Erickson, "Working with interface metaphors" (pp. called "Interface agents: metaphors with character" by
65-74), which is a practical hands-on guide to designing in- Brenda Laurel (pp. 355-366) and another called "Guides:
terface metaphors (covered later in this book), and Ted Nel- characterizing the interface" by Tim Oren et al. (pp.
son's polemic, "The right way to think about software 367-382).
design" (pp. 229-234), which is a scathing attack on the use BANNON, L. (1977) "Problems in human-machine interac-
of interface metaphors. tion and communication." Proc HCI'97, San Francisco.
JOHNSON, M. AND LAKOFF, G. (1980) Metaphors We Live Bannon presents a critical review of the agent approach to
By. The University of Chicago Press. Those wanting to find interface design.
out more about how metaphors are used in everyday con- MIT's Media Lab (www.media.mit.edu) is a good starting
versations should take a look at this text. place to find out what is currently happening in the world of
There are many good articles on the topic of interface agents, wearables, and other new interaction paradigms.
agents. A classic is: