Introducing User-Centered Systems Design - Foundations for Designing User-Centered Systems - page 19

because humans reason creatively and inductively through association and using
mnemonics, they could easily beat computers on standard general knowledge tests.
However, since the advent of the Internet, which represents a massive database of
general knowledge that has been supplied through untold hours of human content
contribution and improvements in computational processing power and search
algorithms, it is possible for a machine, Watson, to beat a human at such tests.
What we see in this example is that the notion of even what a machine is can
change over time. Therefore, when considering allocation of processing activities
between humans and computational devices, we need to ensure we are using the
most appropriate sense of the term machine.
We also include simple interaction at the behavioral level. For example,
Norman ( 2013 ) has written about ''forcing functions''. These are aspects of
devices that suggest particular uses or styles of interaction. In some cases, affor-
dances force a particular style of interaction. One of Norman's favorite examples
is door design. Doors with handles suggest that they should be pulled, while doors
without handles suggest that they should be pushed. A forcing function would be
where the door with the handle cannot be pushed, thus forcing that it be pulled.
Violation of these affordances (doors that can only be pushed yet have handles)
leads to confusion. Perceptual issues sit between the behavior and cognition. For
example, PowerPoint presentations where the font is too small means people
cannot read the content unless they move physically closer (Kosslyn 2007 ).
In addition to noting the basic foundations that explain how people behave, we
also have to consider why people behave in the way that they do. The motivation
that people have for performing particular tasks will vary, partly depending on
internal factors, but also partly on external factors (e.g., is it a work task, is it being
carried out in an informal setting, and so on.)
1.4.3 Cognition
The cognitive level uses the previous two levels and builds upon them. On this
level, how the user thinks about their task and the system is considered, as well as
both basic and higher level cognitive capabilities. These capabilities include a
variety of memory systems that the user has available, as well how these memories
are organized and how they are used by a central processor. Higher level con-
structs include how attention and learning affect these structures and processes.
Some example cognitive issues are shown in Table 1.6 .
Work on the cognitive level will often involve observation of the tool/envi-
ronment in use, asking the question of why and when is it used? This is necessary
because users will vary more on this level of analysis than on the previous two
levels. On this level, people will vary based on previous experience, which can
include training, formal education, previous use, personal style, and strategy
choice.