CS252. User Interface Design
Solutions to Homework 2 - Chapters 3 and 4 in Jordan book
Questions from Chapter 3
1. Explain the difference between consistency and compatibility using examples
from your experiences with software interfaces.
Answers will vary. The important distinction to make is that consistency
has to do with how the steps needed to carry out one task (using one portion
of the interface) relate to the steps needed for another task, while
compatibility reflects how well interface operations match up with those
in other products or in the "outside world."
An example could be that in Excel, the actions needed to calculate
a sum and an average are almost identical: in the cell where the sum/average
will be displayed, you indicate that the formula should be "SUM(" and highlight
the cells to be summed,; all that changes to compute the average is that you
specify a different function name. While this is compatible with the way
things are done in Lotus, it is not particularly compatible with the "outside
world," where a sum just requires successively adding values, while an
average requires adding them, then counting how many values there were, then
dividing the sum by the count.
2. Which user resources are involved in each of the following types of
- playing a computer game involving a joystick
- watching a video clip on your computer screen
- typing a letter using word processing software
- composing music using a software package
- playing a computer game involving a joystick: involves eyes to
watch the screen plus hands on the joystick (and possible ears,
if audio is involved)
- watching a video clip on your computer screen: eyes to watch
the screen and ears to hear the audio track
- typing a letter using word processing software: eyes to watch
the screen, plus hands on the keyboard
- composing music using a software package: eyes to watch the
screen, ears to hear the tones echoed back, plus hands
on the keyboard and/or mouse
6.Name three ways that Visual Basic prioritizes the functionality and
information presented to the user.
VB uses the concept of priorization extensively. Examples include:
- There are many separate menus and they are organized hierarchically,
so the user sees only a small subset of functionality at a time.
- Complex operations are grouped together and presented in separate
popup dialogs; they remain invisible until they are needed, and
disappear once the operation is complete.
- Toolbars (at top and side) present the most commonly needed features.
- Separate windows control the source code and the form appearance; only
one is shown at startup; the user must explicitly bring up others.
- Since project groups may be very complex, a "project explorer" pane
is used so that only one project is visible at a time; the user
navigates through the hierarchy in this pane to see other
- Since a project potentially has many objects, each with its own
properties, the properties pane shows only one object at a time;
the user switches objects using the drag-down list at the top
of the pane.
- Debugging windows are not normally displayed, but are always available;
once the user invokes them, they continue to come up even after
the program has been stopped and then re-started -- this is an
example of using mode to prioritize functionality and
center>Questions from Chapter 4
5. List three reasonable user requirements for the automatic translation
- It must be possible for the user to view either the original and the
translated text, or to switch back and forth between them.
- It should be possible to determine which sentence in the original
document corresponds to a sentence in the translated version.
- It should be possible to translate Spanish that includes idioms from
different Latin American countries, as well as the kind of Spanish
used in Spain proper.
6. For any one of the user requirements you just identified, define two
usability criteria that could be tested empirically.
Examples corresponding to the first requirement:
- Displays must be capable of using English or Spanish character sets,
and switching between them without an obvious pause.
- For documents less that 1 Mb in length, it should be possible to switch
back and forth between the English and Spanish display in less than