Subjective Workload Assessment for On-Hold Telephone Stimuli

Abstract

The goal of this study was to begin to understand the subjective workload reported by users who are placed on telephone hold while listening to a number of different stimuli. Two separate studies were conducted. In the first study, participants were placed on hold while listening to a series of on hold stimuli. On-hold stimuli comprised of silence, natural voices and tones were used. While on hold, they performed a secondary task. In the second study, participants were not placed on hold, but simply performed each of the tasks. The NASA-TLX was used to measure workload in each of the conditions. Results show that there is a significant difference between subjective workload for the different on-hold stimuli, but that the contributions of the secondary tasks were not clear.

Mental Workload Measures of Auditory Stimuli Heard during Periods of Waiting

“…Some evidence for this hypothesis can be found in Kortum et al (2008). One of the conditions used in that study was a silence condition in which the participant was placed on hold and no stimulus was played for the duration of the hold time.…”

“…Because callers are typically engaged in other activities, it becomes important to consider whether the use of auditory progress bars might interfere with the caller's ability to perform these secondary tasks. Recent research has attempted to evaluate how different forms of an APB might impact users' subjective mental workload in these kinds of dual-task situations, but the results have been inconclusive (Kortum, Ling, Su, Peres, and Stallman, 2008).…”

Auditory Progress Bars: Estimations of Time Remaining

“…Moreover, other data shows that listening to different types of sounds results in people over or underestimating the duration of their hold time (Stallmann et al 2008). For these reasons, retrospective time estimations have been used to measure the utility of various APB designs (Kortum et al, 2005;Kortum and Peres, 2006;Peres, Kortum and Stallmann, 2007;Kortum, Ling, Peres, Stallmann, 2008;Kortum et al, in press). Specifically, retrospective estimations are when researchers have callers listen to an APB for a given amount of time, and then ask them to judge the duration of the time they were on hold (Kortum et al, 2005;Kortum et al, 2006;Peres et al, 2007;Stallmann et al, 2008;Kortum et al, 2008;Kortum et al, in press).…”

“…However, this solution is not effective for callers engaged in another task because he or she may mistake the voice giving the announcement as the operator's voice. Ideally, APBs avoid this problem by providing information about the time remaining through the design of the sound itself and avoiding the use of speech (Kortum et al 2005;Kortum et al, 2006;Peres et al, 2007;Kortum et al, 2008). For instance, the progression of the APBs acoustic properties could be mapped in a manner that communicates when the sound will end-or the task will be completed (Kortum et al 2005;Kortum et al, 2006;Peres et al, 2007;Kortum et al, 2008).…”