Analysis of effects of driver/vehicle characteristics on acceleration noise using GPS-equipped vehicles

Researchers have used acceleration noise, defined by the standard deviation of accelerations of a vehicle, as an attempt to measure the quality of traffic flow. As a potential indicator of traffic flow quality, acceleration noise has been considered to be capable of reflecting vehicle/driver–roadway–traffic interactions within a traffic stream. However, this proposition, in particular for the driver/vehicle, has seldom been investigated, mainly due to the difficulty of data collection. This paper reports the results of an analysis of the effects of driver/vehicle characteristics on acceleration noise using global positioning system (GPS)-equipped instrumented vehicle data obtained from four freeway segments. In the analysis, speed models were developed and compared with acceleration noise models. In addition, the effects were investigated by traffic condition levels defined by the density-based level of service.