Classifying and selecting UX and usability measures – Nigel Bevan http://t.co/zhM7ggjP
COST294-MAUSE Workshop: Meaningful Measures: Valid Useful User Experience Measurement. June 2008
Classifying and selecting UX and usability measures
Nigel Bevan Professional Usability Services 12 King Edwards Gardens, London W3 9RG, UK email@example.com www.nigelbevan.com
There are many different types of measures of usability and user experience (UX). The overall goal of usability from a user perspective is to obtain acceptable effectiveness, efficiency and satisfaction (Bevan, 1999, ISO 9241-11). This paper summarises the purposes of measurement (summative or formative), and the measures of usability that can be taken at the user interface level and at the system level. The paper suggests that the concept of usability at the system level can be broadened to include learnability, accessibility and safety, which contribute to the overall user experience. UX can be measured as the user’s satisfaction with achieving pragmatic and hedonic goals, and pleasure.
WHY MEASURE UX/USABILITY?
20% chance that the success rate for a large sample of users might only be 51%. Although summative measures are most commonly obtained from user performance and satisfaction, summative data can also be obtained from hedonic questionnaires (e.g. Hassenzahl et al., 2003; Lavie and Tractinsky, 2004) or from expert evaluation, such as the degree of conformance with usability guidelines (see for example Jokela, et al, 2006).
The most common reasons for measuring usability in product development are to obtain a more complete understanding of users’ needs and to improve the product in order to provide a better user experience. But it is also important to establish criteria for UX/usability goals at an early stage of design, and to use summative measures to evaluate whether these have been achieved during development.