Tree testing is a usability

Usability

Usability is the ease of use and learnability of a human-made object. The object of use can be a software application, website, book, tool, machine, process, or anything a human interacts with. A usability study may be conducted as a primary job function by a usability analyst or as a secondary job...

 technique for evaluating the findability

Findability

Findability is a term for the ease with which information contained on a website can be found, both from outside the website and by users already on the website. Although findability has relevance outside the World Wide Web, it is usually used in the context of the web...

 of topics in a website

Website

A website, also written as Web site, web site, or simply site, is a collection of related web pages containing images, videos or other digital assets. A website is hosted on at least one web server, accessible via a network such as the Internet or a private local area network through an Internet...

. It is also known as reverse card sorting or card-based classification.

A large website is typically organized into a hierarchy (a "tree") of topics and subtopics. Tree testing provides a way to measure how well users can find items in this hierarchy.

Unlike traditional usability testing

Usability testing

Usability testing is a technique used in user-centered interaction design to evaluate a product by testing it on users. This can be seen as an irreplaceable usability practice, since it gives direct input on how real users use the system...

, tree testing is not done on the website itself; instead, a simplified text version of the site structure is used. This ensures that the structure is evaluated in isolation, nullifying the effects of navigational aids, visual design, and other factors.

Basic method

In a typical tree test:

1. The participant is given a "find it" task (e.g., "Look for brown belts under $25").
2. They are shown a text list of the top-level topics of the website.
3. They choose a heading, and are then shown a list of subtopics.
4. They continue choosing (moving down through the tree) — drilling down, backtracking if necessary – until they find a topic that satisfies the task (or until they give up).
5. The participant does several tasks in this manner, starting each task back at the top of the tree.
6. Once several participants have completed the test, the results are analyzed for each task.

Analyzing the results

The analysis typically tries to answer these questions:

• Could users successfully find particular items in the tree?
• Could they find those items directly, without having to backtrack?
• If they couldn't find items, where did they go astray?
• Could they choose between topics quickly, without having to think too much?
• Overall, which parts of the tree worked well, and which fell down?

Tools

Tree testing was originally done on paper (typically using index cards), but can now also be conducted using specialized software.

External links

• Treejack, tree-testing software by Optimal Workshop
• C–Inspector, tree-testing software by Steffen Schilb
• Dave O'Brien (Dec 2009). Tree Testing: A quick way to evaluate your IA