UXI (User Experience Index)

The User Experience Index (UXI) is a value (0-5) which measures the overall performance and health of an application, based on several inputs: the number of crashes per hour out of the total usage time, the percentage of hang time out of the total usage time, the percentage wait time out of the total usage time. For web applications, it also uses the percentage of web page errors out of all page loads, and the average page load time. These ingredients come together to represent the overall experience of a user.

For each element of the UXI, we determine a narrow range of meaningful results, beyond which it is flattened to either zero or the maximum. For example, a regular application should have 0% hang time, so anything above 5% would be unacceptable, therefore the hang time index would be zero, which drastically lowers the overall UXI score for that application.

Definition of UXI

This index is an absolute (not relative) measurement, since it does not depend on baselines which may vary between applications or locations, equivalent to the global energy star ratings used for appliances. Therefore the system can accurately display a single objective measurement across several attributes. For example, it can display this index for a single user on a single application, or many users on a single application, or many users on many applications.

This measurement is NOT connected to activities and their response times, which applies only to managed applications, or to the quality of calls (MOS) in Skype for Business and Lync.