DESIGNS THAT FIT - Human-Computer Interaction and Management Information Systems: Foundations - page 188

comprehensive view of HCI. Inherent in the systems perspective is the idea of compatibility between
subsystems in order to produce a concerted joint goal. Furthermore, the idea of compatibility between
the human and computer subsystems implicitly assumes an efficient allocation of tasks that is based
on the relative strengths and weaknesses of the subsystems. For example, computers should be
designed to perform tasks that humans perform inaccurately or inefficiently. Fit between human and
computer subsystems is therefore seen as a necessary condition for goal achievement.
In contrast to the systems perspective of HCI, the dialog-partner perspective regards the human
and the computer as partners to dialog in a communication process in which both parties act as
senders and receivers of messages. The major implication of this perspective is the pursuit of
improving the dialog, mainly on the basis of how people communicate and how they fit the way they
communicate to the prevailing circumstances. (Below I expand on the specific implications of this
perspective on designing fit.)
The tool perspective regards the computer as offering a tool kit with which the user, who is in
control, can produce some product using materials as inputs. This perspective is important in
design because it underscores the need to fit the tool to the attributes and limitations of the users
working in specified situations so that the user can work effectively, efficiently, and comfortably.
Finally, the media perspective treats the computer as a medium through which humans com-
municate. Importantly, this view stresses the collective context of use. The media perspective has
implications for design at the level of the meaning communicated between people, emphasizing
language and striving for perfect understanding between communicators. In particular, this per-
spective emphasizes the need to fit the medium to the context of the communication, to the type
of information communicated, and to the communicators involved.
Thus, each of these perspectives can add, in general, to the design of HCI, and, in particular, to
the role of fit in design. Depending on the perspective held (e.g., a tool perspective or a systems
perspective), fit can be seen as the adaptation of the computer to characteristics and desires of the
user or as the mutual adaptation of both the computer to the user through design and the user to
the computer through training. Furthermore, depending on the perspective, different elements of
the computer system are fitted to different attributes of the task and the user (the different emphases
in each of the four perspectives are elaborated in the conclusion). I begin, however, with a demon-
stration of the implications on fit of the communication and media metaphors.
Borrowing from the world of communication is especially useful in setting the scope of our
discussion. A significant part—some may argue all—of human-computer interaction has to do
with communication between the user and the computer. It is therefore fruitful to learn from human-
human communication. Effective communicators adapt their communication to their audience
and the prevailing circumstances. In other words, they seek a fit among the different elements of
communication: the message and medium of communication, the receiver of the communication,
the goal of the communication, the physical and social context, etc. Consider several examples.
Example 1: A speaker realizes the room is noisy so she raises her voice. Example 2: A speaker
knows the message is sensitive and potentially embarrassing, so she seeks a private channel of com-
munication. Example 3: Knowing the listener's young age, the speaker chooses bright colors and
animation for her presentation. Example 4: A speaker knows that the listener needs the message
in order to decide which direction to continue driving, so she provides the location of the destina-
tion relative to the listener's current location. Example 5: Seeing the listener frowning, the speaker
explains the message in more detail with more concrete examples. Example 6: Seeing the lis-
tener's anguish at the bad news, the speaker expresses sympathy.
Projecting these ideas from human-human communication to human-computer interaction is
straightforward. HCI examples that correspond to the six communication examples above could