Explorations on Single Usability Metrics
Michael Van Waardhuizen, Jennifer McLean-Oliver, Nancy Perry, Joe Munko · 2019
A long-term summative evaluation program was undertaken at Microsoft. This program focused on generating a Single Usability Metric (SUM) score across products over time but encountered a number of issues including error rate reliability, challenges establishing objective time-on-task targets, and scale anchoring. These issues contributed to making SUM difficult to communicate, prompting exploration of an alternative single usability metric using simple thresholds developed from anchor text and inter-metric correlations.