On the relationship between pedestrian gap acceptance and time to arrival estimates

Area of Science:

• Human-Computer Interaction
• Cognitive Psychology
• Transportation Safety

Background:

• Pedestrian street crossing decisions rely on assessing safe gaps.
• Vehicle approach speed influences gap acceptance, with faster speeds leading to riskier choices.
• The role of time to arrival (TTA) versus physical distance in these decisions is debated.

Purpose of the Study:

• To investigate the relationship between gap acceptance and time to arrival (TTA) estimation.
• To determine if subjective TTA estimates explain the influence of vehicle speed on pedestrian crossing decisions.

Main Methods:

• Two experiments presented participants with videos of approaching vehicles.
• Participants made crossing decisions or estimated TTA.
• Analyzed the impact of objective vs. subjective time gaps on gap acceptance.

Main Results:

• Confirmed typical effects: smaller gaps accepted at higher speeds, lower TTA estimates at lower speeds, and larger gaps for older pedestrians.
• The influence of vehicle speed on gap acceptance decreased significantly when using subjective TTA estimates.
• Systematic distortions in TTA estimation were observed.

Conclusions:

• Subjective TTA estimates, rather than objective measures, appear to better explain the effect of vehicle speed on pedestrian gap acceptance.
• Pedestrian crossing behavior is influenced by perceived, not just actual, time to arrival.
• Understanding TTA estimation biases is crucial for improving pedestrian safety.