Some Characteristics of the Track of an Automobile Driven at Two Different Speeds

10 Ss drove an automobile over a 3-mile long portion of an interstate highway, once at 45 mph and once at 65 mph. A photoelectric device mounted on the automobile recorded its lane position every 3.81 ft. throughout each trip. Results showed that the mean maintained position was significantly farther from the right edge of the pavement at the 65 mph speed and that dispersions about the mean were greater at 65 mph. Distributions of position measurements were essentially normal at both speeds. It was concluded that measurement of the entire track of a vehicle provides several advantages not possessed by techniques that study lane position at discrete points on the highway.