title: Alerts for in-vehicle information systems: annoyance, urgency, and appropriateness.
abstract: OBJECTIVE
  This study assesses the influence of the auditory characteristics of alerts on perceived urgency and annoyance and whether these perceptions depend on the context in which the alert is received.
  
  
  BACKGROUND
  Alert parameters systematically affect perceived urgency, and mapping the urgency of a situation to the perceived urgency of an alert is a useful design consideration. Annoyance associated with environmental noise has been thoroughly studied, but little research has addressed whether alert parameters differentially affect annoyance and urgency.
  
  
  METHODS
  Three 2(3) x 3 mixed within/between factorial experiments, with a total of 72 participants, investigated nine alert parameters in three driving contexts. These parameters were formant (similar to harmonic series), pulse duration, interpulse interval, alert onset and offset, burst duty cycle, alert duty cycle, interburst period, and sound type. Imagined collision warning, navigation alert, and E-mail notification scenarios defined the driving context.
  
  
  RESULTS
  All parameters influenced both perceived urgency and annoyance (p < .05), with pulse duration, interpulse interval, alert duty cycle, and sound type influencing urgency substantially more than annoyance. There was strong relationship between perceived urgency and rated appropriateness for high-urgency driving scenarios and a strong relationship between annoyance and rated appropriateness for low-urgency driving scenarios.
  
  
  CONCLUSIONS
  Sound parameters differentially affect annoyance and urgency. Also, urgency and annoyance differentially affect perceived appropriateness of warnings.
  
  
  CONCLUSIONS
  Annoyance may merit as much attention as urgency in the design of auditory warnings, particularly in systems that alert drivers to relatively low-urgency situations.
authors.affiliation: University of Iowa, Iowa City, Iowa, USA.
authors.forename: Dawn C
authors.initials: DC
authors.lastname: Marshall
authors.forename: John D
authors.initials: JD
authors.lastname: Lee
authors.forename: R Albert
authors.initials: RA
authors.lastname: Austria
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control; D000161:Acoustic Stimulation / Q000379:methods*; D000293:Adolescent; D000328:Adult; D001288:Attention; D001307:Auditory Perception; D001334:Automobile Driving / Q000523:psychology; D006801:Humans; D011930:Reaction Time; D017751:Safety Management; D013016:Sound; D013018:Sound Spectrography