Good Defaults

Examples:

A PC login screen with the last user's name still in the "User name:" field
A phone menu which, if you don't press any number, puts you through to a human operator who can help you
Refrigerator controls which give you a "medium coldness" setting by default

Context: The user should fill in information on a Form (or change settings via a Control Panel), and some of the data fields can be given reasonable default values. This can happen within many different subpatterns: Choice from a Small Set, Choice from a Large Set, Sliding Scale, Forgiving Text Entry, etc.

Problem: How does the artifact indicate what kind of information should be supplied?

Forces:

Filling out forms is not inherently a fun activity; don't prolong the agony by making the user do unnecessary work.
The user may have no clue what kind of value to supply, from the given context.
The user may be perfectly happy with the default behavior or values, with no desire to change it; but they may want to know what the default values are.
"Correct" values for some unfilled fields may be difficult or impossible for the artifact itself to figure out.

Solution: Supply reasonable default values for the fields in question. Show these defaults to the user, so that they know they aren't required to fill them in. Indicate clearly that the value can be changed by the user, if they so desire.

Resulting Context: You need to choose the correct default value. The actual value you use will depend entirely upon the particulars of the artifact, of course, but keep in mind such principles as minimal work (pick a default value that most of your users will be OK with), adaptability (change a default value to be consistent with information the user has already supplied), and representativeness (make it a good example of "correct" input).

Comments to: jtidwell@alum.mit.edu
Last modified May 17, 1999