Feedback Preferences and Impressions of Waiting Russell J. Branaghan and Christopher A. Sanchez, Arizona State University, Mesa, Arizona Objective: Three experiments examined the effects of various feedback displays on user preference, apparent waiting durations, waiting time reasonableness, and other user experience measures. Background: User interface guidelines advocate keeping users informed about system status; however, the duration estimation literature shows that focusing on temporal information makes the wait seem longer. How can designers reconcile these issues? Methods: In three experiments, students chose movies from a simulated movie database and then were shown feedback displays (static, sequential dots, constant-rate progress bars, or variable-rate progress bars) for different durations. Users judged how reasonable the wait was and how long it lasted and then ranked their preference for the dialogs. Results: The pattern of preference results was different from duration-related judgments. Users preferred feedback that provided more information. On the other hand, when judging duration, users perceived simpler interfaces as being most reasonable. Conclusion: Different types of feedback are required for reducing perceived wait and increasing preference. Ratings of wait time reasonableness were consistent with the attentional gate theory of prospective timing; attention-demand- ing activity caused the wait to seem less reasonable. Preference, on the other hand, requires keeping users informed about the progress of operations. Application: Users prefer more feedback rather than less, even if it makes the wait seem less reasonable. However, the constant progress bar performed at the top of both reasonableness and preference, keeping users informed without increasing arousal or focusing attention on temporal stimuli. Other options are also discussed to make duration perceptions more reasonable. Address correspondence to Russell Branaghan, Arizona State University, Applied Psychology, Room 150D Santa Catalina Hall, 7271 E. Sonoran Arroyo Mall, Mesa, AZ 85212; russ.branaghan@asu.edu. HUMAN FACTORS, Vol. 51, No. 4, August 2009, pp. 528-538. DOI: 10.1177/0018720809345684. Copyright © 2009, Human Factors and Ergonomics Society. INTRODUCTION Unfortunately, waiting is a common occur- rence when using interactive devices, espe- cially ones that access media and information from the World Wide Web. It has been demon- strated that users can begin to lose interest in the task at hand with wait periods as short as 2 s (Nah, 2004). However, users tend to be more satisfied when provided with feedback confirm- ing that the device is processing their request. These simple premises are the basis for user interface guidelines, which suggest keeping users informed during waiting periods (Nielsen, 1994; Shneiderman & Plaisant, 2005; Wickens, Lee, Liu, & Becker, 2004). Delays and Computer Interaction Slow response is a major source of annoy- ance with computing. Even as broadband and other high-speed data streams connect devices, growing graphic and multimedia content miti- gate speed improvements. As a result, download and response times remain primary concerns for most computer users. There are several good reasons for users to be frustrated by such delays (Ryan & Valverde, 2006). When people use computers (even if just for entertainment), their activities tend to be goal directed. Achieving these goals requires some measure of planning, and computer delays can force the user to “make a mental note” to which at ARIZONA STATE UNIV on March 16, 2010 http://hfs.sagepub.com Downloaded from