7. design rules

EXERCISE 7.11 [extra - not in book]

The following design criterion applying the principle of learnability is part of a set of design criteria given to a student for a project to produce an electronic fashion consultant.

Learnability: ease of learning and use

  • How easy is the system to use?
  • Are the functions intuitive and the features easily seen?
  • Can the user perceive what will happen after a command is issued?
  • Doing user tests on 3 interface designs will assist in focusing our efforts.

Provide some constructive criticism suggesting how this design criterion could be improved.

answer available for tutors only

There are two main problems with this design criterion.

First, it is too vague. Learnability is divided into a number of other sub-properties: predictability, synthesizability, familiarity, generalizability, consistency. The criteria should be more specific. For example, is learnability important for novice users, or for experienced users who want to learn more and new features of the system? Will the learnability be achieved through consistent implementation of similar features, or will it leverage off some metaphor or other familiar source of information that the design team is assuming about its users?

The second main point is that though there is some attempt to express this criterion in a measurable fashion, it needs to be done in a way that is specific to the application itself. How is learnability important for an electronic fashion consultant?

Other exercises in this chapter

ex.7.1 (ans), ex.7.2 (ans), ex.7.3 (open), ex.7.4 (ans), ex.7.5 (ans), ex.7.6 (ans), ex.7.7 (tut), ex.7.8 (tut), ex.7.9 (open), ex.7.10 (tut), ex.7.11 (tut), ex.7.12 (tut), ex.7.13 (tut)

all exercises for this chapter