Behavior: Basic Psychology of the User - Foundations for Designing User-Centered Systems - page 117

to say out loud or to categorize, or objects to name. The items should be
prepared in both black and white and color.
Have a group of users do the task with both the black and white and color
objects. Record the time it takes them to do the tasks and how many errors
they make. You may have to vary the size of the objects to get these measures
to vary.
In addition to reporting what you find, you should indicate what the find-
ings mean about displays and the use of color.
4.2 Choose six icons from popular or not so popular software packages. Also
choose six menu items that are words (e.g., Format: Frame, File: Save, Insert:
Date, Message: Reply, View: Master Document, Tools: Goal Seek, Edit:
Copy) or choose icons from an online training system or training system such
as Rosetta Stone.
Ask six to ten people to tell you what they think each icon and each menu
item will do or represents. Summarize your results in a table as well as a set of
suggestions for how to design interfaces. If you have access to a different
population of users, people from different cultures, physical abilities, or ages,
run the study on that population as well and compare their responses to your
classmates.
4.3 Explain how signal detection theory can be used to analyze web site reading
and searching. Based on this analysis, provide three suggestions for your
favorite search engine or web site that includes search.
4.4 Redraw the signal detection curve in a big format. Either make the curves big,
or put the signal and noise on separate lines to that they are easy to work with.
Label the parts of the curves that make up hits, misses, false alarms, and
correct rejections.
Redraw the curves with the signal being smaller. How does this affect the
setting of the threshold, or how does it influence how to set the threshold for a
given ratio of hits to false alarms?
4.5 Choose an online, social web site, such as Facebook, YouTube, or Yelp. Sketch
several tasks that can be done by users with the site. Describe the intrinsic and
extrinsic motivation(s) for users to perform those tasks. Do the same for an
online course site, and for an online game. Note some insights that arise.
References
Bowmaker, J. K., & Dartnall, H. J. A. (1980). Visual pigments of rods and cones in a human
retina. Journal of Physiology, 298, 501-511.
Catchpole, K., McKeown, J. D., & Withington, D. J. (2004). Localizable auditory warning pulses.
Ergonomics, 47(7), 748-771.
Chaiklin, S. (2003). The zone of proximal development in Vygotsky's analysis of learning and
instruction. In A. Kozulin, B. Gindis, V. Ageyev, & S. Miller (Eds.), Vygotsky's educational
theory and practice in cultural context (pp. 39-64). Cambridge: Cambridge University.
Csíkszentmihályi, M. (1990). Flow: The psychology of optimal experience. New York, NY:
Harper and Row.