Travel information continues to receive significant attention in the field of travel behaviour research, as it is expected to help reduce congestion by directing the network state from a user equilibrium towards a more efficient system optimum. This literature review contributes to the existing literature in at least two ways. First, it considers both the individual perspective and the network perspective when assessing the potential effects of travel information, in contrast to earlier studies. Secondly, it highlights the role of bounded rationality as well as that of non-selfish behaviour in route choice and in response to information, complementing earlier reviews that mostly focused on bounded rationality only. It is concluded that information strategies should be tailor-made to an individual's level of rationality as well as level of selfishness in order to approach system-optimal conditions on the network level. Moreover, initial ideas and future research directions are provided for assessing the potential of travel information in order to improve network efficiency of existing road networks. ARTICLE HISTORY

This study examines to what extent travel information can be used to direct travelers to system-optimal routes that may be sub-optimal for them personally, but contribute to network efficiency. This is done by empirically examining determinants of travelers' compliance with social routing advice. To that end, we conducted both a stated choice experiment and a revealed choice experiment (which also collected stated intentions and motivations for revealed behavior). Results from the stated choice experiment indicate a significant difference in compliance behavior across different information frames, societal goals, sizes of travel time sacrifices and personality. These findings are less evident from results based on analysis of revealed choices; i.e., the main motivation for revealed compliance seems to be an intrinsic motivation to contribute to improved throughput, while the main motivation for non-compliance relates to perceived traffic conditions. Moreover, the size of the travel time sacrifice seems not that important as expected. Nonetheless, comparing stated intentions with real-world behavior suggests that a relation between intention and compliance frequency does exist.

Information-based demand measures using social routing advice are receiving increasing attention, as they are expected to be successful in reducing the traffic congestion. Such measures direct travelers toward routes that benefit the road network. As such, some travelers need to act socially and take a detour. This paper explores the impacts on network performance and equity that result from the application of a social routing service. We complement the existing work by using a largescale real-world road network, by assessing impacts on the individual level and by discussing our findings in the light of observed individual compliance behavior obtained from a field experiment. Our results show that 3.6% of total travel time within our road network could be reduced when all trips are made in compliance with the received advice. However, based on the observed compliance behavior, a social routing service is expected to direct only a minority of travelers toward social routes. We show how the attained travel time savings vary with the assumed compliance rate, e.g., to achieve 50% of the potential travel time savings, about 30% of travelers need to be willing to take a detour. Moreover, we find that lower the compliance among travelers, the more the social travelers need to compensate for the selfish behavior of others by taking longer detours. Finally, we demonstrate that the impacts on network performance and equity highly depend on the spatial distribution of social travelers among origins and destinations.

Route choice behaviour in response to travel information receives increasing attention within travel behaviour research. This study contributes to the literature by generating insights into the effect of travel information on day-today route choice behaviour based on largely explorative analyses using route choice data obtained from a real-world experiment. As such, our study complements confirmatory stated preference and laboratory experiments. We find that the provision of travel information leads to a decline in switching propensity and a higher probability that the shortest route is chosen. Furthermore, we identified six behavioural profiles, varying from switch-averse to switch-prone. Travel time information seems to influence travellers' propensity to shift from one profile to another across different OD-pairs. Our results contribute to understanding of the effect of travel information on route choice behaviour, and as such help inform the design of effective information-based demand management measures.