Civilization advances by extending the number of operations we can perform without thinking about them.
- Alfred North Whitehead, British philosopher
Learnability signifies how quickly a new user can begin efficient and error-free interaction with a system.
Why is Learnability Important?
Case study 1:
A telecommunications company implements a new core information system with 6000 users. For each hour saved in training the company saves $300,000.
Case study 2:
The Ajax Auto Parts Company sells auto parts over the Internet. Its customers must use its Web-based Internet store application without any training. The web user interface is non-intuitive and hard to learn. Ajax's customers give up and buy from another vendor with a more usable web site.
How Does Learnability Relate to Usability?
Learnability is one of the attributes of a software product that contribute to general usability.
What is usability?
- Easy to learn
- Efficient to use
- Easy to remember
- Few errors
- Subjectively pleasing
ISO Standard 9241-111 provides the following guidance on measuring learnability:
- Number of functions learned
- Percentage of users who manage to learn to criterion
- Time to learn to criterion
- Time to re-learn to criterion
- Relative efficiency while learning
- Rating scale for ease of learning
Other measures include:
- Error counts
- Error recovery time
- The time that a new user needs to reach a predefined level of proficiency.
Improving the Learnability of a User Interface
Researchers have identified seven factors that impact the learnability of a user interface.
|Visibility of commands and menu options
Make commands and menu options highly visible and easy to find. For example near the object that they impact - a right click on an object displays a list of available operations.
||Provide feedback messages that a user command has succeeded or advise of failure.
|Continuity of task sequences
||When a user starts a command from a menu or by clicking on an icon, provide direction until the task sequence is complete. For example, by providing a
sequence of dialog boxes or instructions in a status bar. Do not require users to jump from one menu to another while performing a single task.
||Use design conventions that are common to office, web, or CAD software products. For example the common menu structure: Edit > Paste
||Provide enhanced descriptions for user interface components: dialog
boxes, fields that require input and image details. For example, a user password registration field is labelled "password must be > 6 characters and have letters and numbers"
|Context sensitive help
||As part of the user interface, provide contextual help to assist the user in overcoming problems.
||Avoid operations that do not succeed because of some simple and predictable mistake. Provide guidance if an inappropriate command is activated or enable commands only when they can be used in the correct context.