HONS 02/07
Improving Task Switching Interfaces
Keith Humm
Department of Computer Science
University of Canterbury
Abstract
Most interfaces for switching between tasks require slow, visual searches of candidates,
where each candidate must be scanned in turn. We developed a logging tool
for task switching actions and undertook a log-based study with eleven participants
to empirically characterise task-switching behaviour, finding Zipfian distributions
for window and application switching, and significant differences in interface use
between single and dual monitor users. We then used this data to assist in designing
a new interface (Spatially COnsistent Thumbnail Zones or SCOTZ) to allow
rapid task-switching performance by utilising spatial memory. In a formal evaluation
against three mainstream interfaces under four workspace conditions, SCOTZ
attained the lowest mean times for all conditions and scaled better with workspace
load, obtaining a significant difference under high workspace load. We conclude with
a recommendation for using SCOTZ at all workspace loads, and suggest it be implemented
and tested in a real-world environment.