You'll Never Walk Alone: Effects of Vehicle Yielding, eHMIs, and Pedestrian Position on Perceived Crossing Risky

Alam, M. S., Dey, D., Martens, M., Bazilinskyy, P.

Submitted for publication. (2026)

ABSTRACT This virtual reality study examined how pedestrian spacing and relative position influence perceived crossing risk during encounters with an automated vehicle. Fifty participants completed a within participant experiment that varied vehicle yielding, conditional external Human-Machine Interface (eHMI) logic, relative pedestrian order, and five centre to centre spacings from 2 to 10 m. The participants remained stationary on the kerb and continuously pressed a controller trigger whenever they judged that initiating a crossing would be unsafe. The primary outcome was the percentage of a fixed five second interval before vehicle passage that was classified as unsafe. A participant clustered marginal binomial model showed that yielding reduced predicted perceived unsafety time by 38.7-52.7 percentage points across the four eHMI and relative order contexts, with Holm adjusted p<0.001 in every context. Conditional eHMI logic reduced perceived unsafety by 9.30 percentage points in yielding trials where the participant was first in the vehicle's path (95% CI [-14.85,-3.75], Holm adjusted p=0.004). No statistically reliable eHMI effect was found in either non-yielding order condition or in the yielding trials where the avatar was first. The full model indicated an association between spacing and relative pedestrian order, but analyses that held the participant's position constant or aligned the data to vehicle events did not support a consistent independent spacing effect. These findings show that vehicle yielding was the dominant influence on perceived crossing risk, while the effects of conditional eHMI logic and pedestrian configuration depended on the interaction context.