Divide the User Profile into Distinct Categories

The user profile describes the range of skills, behaviors, and experience that make up the entire universe of target end users. Every end user should fall somewhere within that spectrum However, you are not interested in individuals alone. Instead, you should identify entire groups of end users who share many of the same characteristics on the user profile. These groups, sometimes identified by similar occupations or job titles but often as roles (for example, "frequent traveler/' "club member," "voter," or even "patient," "parent," "vendor," or "client"), will use the product and its support materials in different ways and for different purposes. This is also where your classifiers come in. Use those to help you group users into categories. It is important that you understand the user profile for each target audi- ence. For example, the hotel reservations web site previously mentioned is intended for both rewards members and travelers who are not rewards mem-

bers (our classifiers); each group may use the site differently. If you were testing that web site, you would want to select some members and some non-members. The proportion depends on the priorities of the business and the objectives and goals for the study. You don't have to try to match the proportions in the target market segments.

Or, suppose you were responsible for testing a banking system that both tellers and "back office" staff members will use. You will want to have some tellers who will use the system for performing daily customer transactions. 

You will also want to have some "back office" staff members who will use the system to generate reports and conduct different analyses. The tasks of the two groups are different.

Each group will have similar characteristics when compared to other members of their group, although with varying levels of expertise. With each group, make sure that you are representing these varying expertise levels, if any. For example, test some novice tellers, some experienced tellers, some novice "back

office" staff, and some expert "back office" staff. Suggestions for how many of each type to include are discussed later in this chapter.

In the hotel reservations web site example, rewards members are likely to be very experienced with the site and non-members are likely to have less experience with the site. But you want both groups of users to cover a range of levels of previous experience with the site. Or you may assume that participants'

overall travel booking experience is more important than their direct experience with your site. In that case, you might want to classify the participants based on the frequency with which they book accommodations in the course of a year, or whether most of their travel is leisure or business-related, again depending on the objective and goals of the test. To represent these different skill levels, you may want to use a matrix test design, discussed in the next section.