Chapter 9 - key points

We aim for at least 50 participants per user group. 100 is ideal. We’ll need more if each participant is only shown a subset of the tasks.

If we use web ads to get participants, we choose web pages (and even other websites) that target the kinds of users we’re looking for.

Web ads should be designed to attract attention and present an at-a-glance proposition, and should link to a page that briefly explains the study and provides an obvious way to start.