There are many helpful books on usability testing. It is also helpful to know what actually happens in usability tests, including what metrics people collect. I asked MeasuringU newsletter subscribers to answer a few questions about how they measure usability. Sign up for weekly updates at the bottom of this page. In addition to the
There has been a bit of an explosion in remote usability testing tools of late. Some of these companies also offer to recruit and provide you with users who are paid to take your usability test (Usertesting.com, Feedback Army and EasyUsability to name a few). These services allow for quick (almost immediate) feedback from users.
In a usability test you typically collect some type of performance data: task times, completion rates and perhaps errors or conversion rates. It is also a good idea to use some type of questionnaire which measures the perceived ease-of-use of an interface. This can be done immediately after a task using a few questions (post-task
Imagine a marketing department asking for more money to conduct a direct-mail campaign and their only justification was that marketing is a critical business advantage. Now contrast that with an argument that showed that in a previous direct-mail campaign the response rate of 3% was more than twice the industry average and was achieved from
Have you ever watched a user perform horribly during a usability test only to watch in amazement as they rate a task as very easy to use? I have, and as long as I’ve been conducting usability tests, I’ve heard of this contradictory behavior from other researchers. Such occurrences have led many to discount the
How many users will complete the task and how long will it take them? If you need to benchmark an interface, then a summative usability test is one way to answer these questions. Summative tests are the gold-standard for usability measurement. But just how precise are the metrics? Just as a presidential poll uses a
Minimize Lurking Variables Getting Warmed Up Without task randomization, so-called lurking variables can taint your data–usually not enough that it’s devastating but often it’s noticeable. One lurking variable when analyzing task times is the user’s tendency to perform better on the later tasks and worse on the earlier tasks. It’s human nature: someone hands you
If you compare the sigma value on this site with other values published in most six sigma literature, it’s important to know that a 1.5 σ “shift” is usually added. For example, if you see a sigma value of 1.08σ on measuringusability.com and want to compare it to other sources then add 1.5. The resulting
