40 participants is an appropriate number for most quantitative studies, but there are cases where you can recruit fewer users.
GUI screen components, workflows, user types, design patterns, and ways of interacting with complex data
Raluca Budiu is Director of Research at Nielsen Norman Group, where she oversees the group's research-related activities and serves as editor for articles published on NNgroup.com. Raluca consults for clients from a variety of industries and presents tutorials on mobile usability, UX for responsive websites, quantitative usability methods, cognitive psychology for designers, principles of human-computer interaction, the design of desktop applications. Raluca coauthored the NN/g reports on tablet usability, mobile usability, iPad usability, and the usability of children's websites, as well as the book Mobile Usability. She served as a judge for GSMA Global Mobile Awards 2012-2018 and Tabby Awards 2013.
Raluca previously worked at Xerox PARC, doing research in human-computer interaction. At PARC, she built computational models of how people search for information in visualizations of large data structures. She also explored new ways of measuring information scent and conducted research on interfaces for social bookmarking systems and on the cognitive benefits of tagging.
Raluca was also a user researcher at Microsoft Corporation, where she explored future directions and made strategic recommendations for incorporating user-generated content and social web features into MSN.
Raluca has authored many articles in academic journals and conferences on human-computer interaction, psychology, and cognitive science. She holds a Ph.D. from Carnegie Mellon University.
GUI screen components, workflows, user types, design patterns, and ways of interacting with complex data
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