Longer Delays in Rehearsal-based Interfaces Increase Expert Use

Abstract

Rehearsal-based interfaces are designed to encourage a transition from novice to expert, but many users fail to make this transition. Most of these interfaces activate novice mode after a short delay, between 150 and 500ms. Our work investigates the impact of this delay time on expert usage and learning in three crowdsourced experiments. The first experiment examines an 8-item marking menu with delay times ranging from 200ms to 2~seconds. Results show longer delays increase successful expert selections. The second and third experiments generalise this result to a different rehearsal-based menu, a desktop clone of FastTap with 8-items and 15-items. Together, our results show that expert use correlates with delay time, but delay time does not always improve menu memorisation. However, imperceptible delays of 200ms harm long term retention of menu items. Designers of rehearsal-based interfaces should take advantage of longer delays to encourage a transition to expert usage.