Event-Based Modeling of Driver Yielding Behavior to Pedestrians at Two-Lane Roundabout Approaches

Drivers are less likely to comply with the “Yield to Pedestrians” sign at roundabouts than at other types of controlled intersections. The aim of this study was to identify the contributing factors affecting the likelihood of drivers yielding to pedestrians at two-lane roundabouts. The analysis used logistic regression to model the likelihood of drivers yielding based on several factors. The models were applied to 1,150 controlled pedestrian crossings at the entry and exit legs of two-lane approaches to six roundabouts across the country. The logistic regression models that were developed support prior research that found that the likelihood of drivers yielding at the entry leg of a roundabout was higher than at the exit. Drivers tended to yield to pedestrians carrying a white cane more often than they did to sighted pedestrians. Drivers traveling in the far lane, relative to pedestrian location, had a lower probability of yielding to the pedestrian. As speed increased, the probability of drivers yielding decreased. At the exit leg of the roundabout, drivers turning right from the adjacent lane had a lower propensity of yielding than did drivers coming from other directions. The logistic regression models also quantified the effect of each of these factors on the propensity of driver yielding. The models included variables that were specific to each study location and explained the impact size of each study location on the probability of yielding. The results of the research can be used to isolate factors that may increase yielding (such as lower roundabout approach speeds) and can feasibly be incorporated into microsimulation algorithms to model driver yielding at roundabouts.