SeeMe at the crosswalk: Before-after study of a pedestrian crosswalk warning system

Abstract

SeeMe is a pedestrian crosswalk warning system with automatic pedestrian detection that is mounted on crosswalk signs. Amber flashing lights are activated when pedestrians are approaching or crossing the crosswalk. The aim is to attract motorists’ attention, to improve yielding behavior and to reduce conflicts. A before-after study with a matched comparison group has been conducted in the Norwegian municipality of Trondheim. Video observations were made at eight crosswalks (four of which were equipped with SeeMe in the after period) of 1825 pedestrian-motorist interactions. On average, yielding rates at SeeMe equipped crosswalks increased by 14% (statistically significant) when changes at the comparison sites are taken into account. However, the results are inconsistent between crosswalks. At two of the crosswalks with SeeMe in the after period, yielding rates increased by 39% (statistically significant), while they decreased by 4% at the other two crosswalks (not statistically significant). There were several differences between crosswalks with increased and unchanged yielding rates: Initial yielding rates (below vs. above 80%), placement of crosswalk signs (immediately at vs. at some distance from the crosswalk) and false alarm rates (30% vs. 57% on average). These factors may have affected the effect of SeeMe on yielding rates, but the number of crosswalks included in the study is too small to generalize the differences between different types of crosswalks. The results do not indicate that SeeMe has negatively affected pedestrian behavior or provoked conflicts. It is concluded that SeeMe may be effective in increasing motorist yielding rates at crosswalks with similar characteristics as in the present study - two-lane roads in residential areas with moderate motor vehicle volumes and speed limits of 50 kph or below - and that high initial yielding rates and high rates of false alarms may limit its effectiveness.