Empirical Estimation of Desired Speed Distributions for Microscopic Traffic Simulation

The desired speed is an important parameter for microscopic traffic simulation. The desired speed can only be directly measured for free-flowing vehicles. However, the average speeds of unimpeded vehicles are systematically lower than the desired speeds of all vehicles. Recently, a new estimation technique in which the speeds of impeded vehicles were considered as censored values was introduced. Here, this method was applied with empirical traffic data in a modified version to estimate desired-speed distributions for two freeway sections in Germany. On the basis of simulation studies the method was shown to deliver consistent desired-speed distributions that allowed for a realistic representation of driver speed behavior within microscopic traffic simulation models.