Characteristics of Speeders on Freeway Ramps

A mobile recording system, with integrated laser speed gun, video from CCD-cameras, digital recorder and auxiliary battery system, was used to observe driving behavior at ramp metering of freeway. Cameras were mounted on a soft shoulder to record: traffic-light status and driving speed from laser speed gun. In addition, one of cameras with telephoto lens focused on windshield of vehicle to catch drivers' characteristics (i.e. age, gender) and vehicle type. After removal of instances of interference, 1538 driving behaviors were recorded. Binary logistic regression was used to examine the risk of speeding as a function of covariates and interaction terms. The results of analysis revealed that the major contributing factors for approaching speed were traffic-light condition, vehicle type and drivers' gender. Analysis of binary logistic regression showed that male van drivers had the greatest speeding propensity in our sample (OR = 24.36). The relative risk of speeding for traveling in passenger absence is four times higher than for passenger presence. Moreover, present results confirm that vehicle- type effects vary with traffic light condition. The results of the present study may provide meaningful information applicable to the design and operation of ramp metering system.