This paper has sought to demonstrate some aspects of day-to-day variability in travel time on an urban freeway. Using detailed travel time and flow data obtained from the DriveTime system installed on Melbourne freeways, it has confirmed and expanded results obtained 25 years ago using much more limited data. It has shown that travel time and travel time variability are both functions of traffic flow, but in subtly different ways. Both measures show different relationships with traffic volumes depending on the prior history of the relationship. The analysis has confirmed the relationship between Congestion Coefficient and Standardised Coefficient of Variation, but has more clearly shown that different regions existing in this relationship, depending on the history of the traffic conditions. The analysis reported in this paper has focussed on day-to-day variability at one point in the network. (Author/publisher) For the covering entry of this conference, please see ITRD abstract no. E210528.
Samenvatting