A method to standardize usability metrics into a single score

Current methods to represent system or task usability in a single metric do not include all the ANSI and ISO defined usability aspects: effectiveness, efficiency & satisfaction. We propose a method to simplify all the ANSI and ISO aspects of usability into a single, standardized and summated usability metric (SUM). In four data sets, totaling 1860 task observations, we show that these aspects of usability are correlated and equally weighted and present a quantitative model for usability. Using standardization techniques from Six Sigma, we propose a scalable process for standardizing disparate usability metrics and show how Principal Components Analysis can be used to establish appropriate weighting for a summated model. SUM provides one continuous variable for summative usability evaluations that can be used in regression analysis, hypothesis testing and usability reporting. ACM Classification H5.2 [Information Interfaces and Presentation]: User Interfaces ? Standardization; Bench...

• Type: Conference
• Year: 2005
• Where: CHI
• Authors: Jeff Sauro, Erika Kindlund
• Keywords: CHI 2005, Disparate Usability Metrics, Human Computer Interaction, ISO Defined Usability, Summative Usability Evaluations