Behavioural analysis of vehicle interactions at priority-controlled and right-hand priority intersections

Abstract

This study analyzes interactions between tow vehicles at right-hand priority intersections and priority-controlled intersectons, which will help to gain a better insight in safety differences between both types of intersections. Data about yielding, looking behaviour, drivers' age and gender, approaching behaviour, type of manoeuvre, order of arrival and communication between road users are collected by on-site observations. Logistic regression models are built to identify variables that affect the probability that a violation against the priority rules occurs, and the probability that a driver looks to the sides when entering the intersection. The number of right-of-way violations is significantly higher at the observed right-hand priority intersection (27% of all intersections) than at the priority-controlled intersection (8%). Furthermore, at the right-hand priority intersection the behaviour of drivers on the lower volume road is more cautious than the behaviour of drivers on the higher volume road, and violations are more likely when the driver from the lower volume road has priority, indicating that the higher volume road is considered as an implicit main road. At both intersection types, there is a higher probability of a right-of-way violation when the no-priority vehicle arrives first, indicating that yielding is partly a matter of "first come, first served". For both intersections, the way a driver approaches the intersection (i.e., stopping, decelerating, or holding the same speed) is highly relevant for the occurrence of a right-of-way violation and he probability that the driver looks to the sides on his approach to the intersection.