Modeling the impact of normative messages on travel behavior change

Prompted by previous research indicating associations between social norms and travel behavior, this study examines the effectiveness of a persuasive normative intervention on car commuters in Cagliari, Italy. The intervention provided (descriptive and/or injunctive) normative statements to encourage a shift from the car to a sustainable travel alternative, namely walking, cycling, or transit, suggested through a Personalized Travel Plan. The construction of an Integrated Choice and Latent Variable model allowed for controlling for level of service, socioeconomic, and psychological variables. Results showed how the injunctive normative message significantly increased public transport intention, particularly when individuals perceived a higher level of behavioral control. However, no significant impact was found for active mobility. Pseudo-elasticity effects showed how the injunctive message had a similar impact as the travel time difference between cars and public transport. This work is valuable for policymakers as it provides insightful best practices for low-budget normative messaging to promote sustainable travel behaviors.