Articles by Martin Schrepp
Dr. Martin Schrepp studied mathematics and psychology at the University of Heidelberg. Since 1994 he has worked as a UX designer and researcher at SAP SE (Germany). His research interests include HCI, UX evaluation methods, statistics, exploratory data analysis, and cognitive sciences.
Response Instability in User Experience Questionnaires
Abstract Surveys are a widely used method for evaluating a product’s user experience. UX surveys include items that ask participants to express their perceptions of various aspects of UX quality including efficiency, learnability, user interface aesthetics, or joy of use. One common item format is a statement to which participants can indicate their level of […] [Read More]
A Comparison of SUS, UMUX-LITE, and UEQ-S
Abstract A loyal customer base depends upon a good user experience over the product’s complete lifetime. Successful products are continuously developed over a long period. Their functionality and complexity typically grow over years, so it is important to measure their user experience continuously. A carefully selected, effective questionnaire can collect quantitative results. But with so […] [Read More]
On the Usage of Cronbach’s Alpha to Measure Reliability of UX Scales
Abstract If, as UX professionals, we measure the user experience of a product with a questionnaire, then scale reliability is important. If the scales of the questionnaire show low reliability, we cannot guarantee stable measurements and should not base important design decisions on such data. There are several methods available to estimate the reliability of […] [Read More]