7: Writing tasks

"But I still haven't found what I'm looking for" - U2

In conventional usability testing, we test a UI by having participants perform tasks - things that we want them to find or to do, just as they would when using that UI for real.

Tree testing is no different. We don’t want the participant to just wander through the tree, giving us their opinions on how easy it would be to find things. We want to simulate what it’s really like to look for something – something specific – using the top-down hierarchy of the site.

So, we ask our participants to start at the top of the tree, and we give them a definite item to find. In fact, we give them a series of tasks – enough to test several parts of the tree in several different contexts, but not so many that they get tired or grumpy, and not so many that they learn the tree more than a real site visitor would.

And our job, for each task, is to make sure that it’s concise and unambiguous. We need each participant to understand the task quickly, and decide it means the same thing that we meant when we wrote it.

In this chapter, we’ll cover how to decide which tasks to include in your tree test, and how to make sure each one is clear to your participants.