Kendrick and MacFarlane

• Procedure

  • Drivers stuck behind a car seemingly not paying attention at a traffic light on a hot day will probably get stressed out and angry
  • During the 12 second period where the green light was on they measured:
  • The number of horn honks
  • The duration of each honk
  • The latency of the honk (how long it took them to start honking)
• Sample

  • 75 drivers (aged 16 to 65) from Phoenix, Arizona were used
  • The experiment was run between April and August
  • Range of temperatures was 31C to 46C
• Results

  • There was a positive correlation between temperature and the amount of time pressing the horn
  • At temperatures over 32C 34% of participants spent 50% of the total green light interval using their horn
  • This provides evidence that temperature is an environmental stressor