ABSTRACT
Statistical Considerations in Usability Testing The intent of this tutorial is to introduce basic statistical methods for determining the sample sizes needed for performing usability studies and for computing confidence intervals. A single course in introductory statistics should be sufficient for understanding the material in this tutorial. The focus of the tutorial is on usability studies that emphasize precise measurement, as well as usability studies intended for problem discovery. Although these methods apply to all user populations, the implications for statistical methods of using older participants are noted where appropriate.
