A Study of Size Effects of Overview Interfaces on User Performance in Virtual Environments

Abstract

Many virtual environment applications use an overview interface showing a survey of the entire space. Little research has been conducted on the size effects of overview interfaces on users’ performance and experiences in virtual environments. The experiment is two (overview interface size) × two (familiarity with mobile devices) between-subject design. Participants completed three tasks on a mobile device and filled out the NASA task load index (TLX) questionnaire as a measure of mental workload. Thirty-two participants were invited to take part in the experiment based on convenient sampling method. The results are as follows: (1) Participants using the smaller overview interface performed significantly better than those using the larger overview interface in the most difficult task. (2) Participants who were more familiar with mobile devices performed significantly better than those who were less familiar with mobile devices in their first visit to the unfamiliar virtual environment. (3) The larger overview interface required significantly more mental workload than the smaller overview interface in terms of the sum score and performance score on NASA TLX. (4) The impacts of overview interface size on users’ performance in the most difficult task and the effort they felt appear to be different for participants with different levels of familiarity with mobile devices. Thus the design of overview interface should consider users’ familiarity with mobile devices.