Road pricing and its individual responses within travel patterns: Lessons from the Akta study

Abstract

While mobility pricing is discussed as a suitable tool for tackling urban traffic problems, its impact on the travel pattern of individuals is largely unexplored. Individual responses to pricing emerge as a number of different changes in attitude. As an example, it involves the reduction in actual trip making, more efficient route choice decisions, trip chaining, and change of destination choice. The analysis of reliable data seems necessary to gain a deeper insight into the personal motivations of behavioural adjustments to the new monetary constraints. The AKTA Copenhagen study – which is part of the EU funded project Pricing ROad use for Greater Responsibility, Efficiency and Sustainability in cities (PROGRESS) – is a real life experiment of road pricing in the greater Copenhagen region (Nielsen and Jovicic, 2003; Nielsen, 2004). During 2001 and 2002, about 400 cars were equipped with GPS data loggers over a period of up to 24 weeks. The on-board systems monitored vehicle movement data for each second and were parallely used to simulate road pricing by displaying cost information for every trip driven. The experiment has already shown significant demand effects with a decrease in daily kilometrage between 0 and 40% depending on the location and the pricing scheme. One of the appealing features of AKTA is the possibility to examine the differentiated pricing system applied against its impact on personal mobility. The paper goes into the question of how road pricing impacts destination choice by deeply analysing the rich GPS trip data set. The panel structure with multiple observations for single cars/drivers allows to investigate the diversity of individual activity repertoires and related travel patterns in both, the control and the pricing periods. In particular, the analysis aims at describing how road pricing affects: − the choice of destinations − the size and structure of activity spaces (according to measures developed for longitudinal travel data by Schönfelder and Axhausen (2004))