The pietree gives you an interactive, holistic view of your participants’ journeys for each task. There’s a lot that pietrees can tell us.
The first thing to do is to review the overall size of the pietree. Is it big and scattered with small circles and lots of lines? Is it small with large circles and not so many lines? Or is it somewhere in between? The overall size of the pietree can provide insight into how long and complex your participants’ pathways to their nominated correct destination were.
Let’s take a look at the pietree below, from our banking website tree test.
The task was: The bank lent you some money a year ago to help you buy a new car. You just got a bonus from work and want to put it towards this debt. Where would you go to do this?
The pietree is fairly small with big circular nodes – these are the parent and child nodes added to the tree when you set your study up. There’s also a thick green line leading from the home page node to the correct destination node. This tells us that participants followed a direct pathway to the correct destination (the one that you set as correct).
You want your participants to be able to reach their goal quickly and directly without navigating down other paths. Using the below as an example, we know that most of our participants had no issues navigating to the correct destination, via the correct path. Therefore, we can be confident that our IA for this particular task is clear.
You’ll notice there are some thinner lines branching out to smaller nodes, we’ll talk about that in the example below.
Now let’s look at another pietree.
The task was: You’re about to go on holiday and want to make sure you’re covered financially if anything bad happens. How would you start the process of doing this?
This pietree is bigger with paths and nodes scattered off in all directions. It shows us that participants took a lot of indirect or winding paths to end up on both correct and incorrect destinations, as well as starting down a certain path then immediately backtracking.
This can indicate that people felt lost or confused when trying to complete the task. It’s shown with red (an incorrect path), blue (the participant has backtracked) on the nodes of the tree, and gray lines leading to smaller yellow nodes (what they’ve nominated as the correct destination).
We can see that, from the offset, participants were confused about where to go and there were a few false starts. The image below shows us that 58.3% of participants started down the wrong path and either continued down that path and nominated an incorrect destination, or they backtracked to go down the right path.
This tells us that perhaps we need to do a bit of work on our labeling to ensure participants can confidently navigate to where they’re meant to go.
Benchmarking a pietree from your existing structure against a proposed new design is a great way to validate your information architecture. This will help you to ensure your IA and content labels are ideal for your users before you move on to wireframing and visual design.