Breaking the Habit of Short Car Trips:A behavioral perspective integrating sensor data,

Short-distance car use remains a significant challenge for the promotion of sustainable transport. Although alternatives such as walking, cycling and public transport are widely available, many people still rely on cars for trips of less than five kilometres, or even one kilometre. These short trips are disproportionately ine!cient, producing high emissions per kilometre and contributing to congestion and noise pollution while consuming valuable urban space. Reducing them is therefore an e”ective strategy for improving urban mobility. However, conventional policies focusing on infrastructure, incentives or restrictions have only had limited and short-lived e”ects. This dissertation takes a behavioral perspective, integrating theories of habit, cognitive bi- ases, and feedback with large-scale empirical data. It combines three complementary studies: (1) a data-driven analysis of 89.4 million trips from 149,709 vehicles across three European countries showing that short car trips are widespread and consistent across di”erent contexts; (2) a study comparing self-assessments from surveys with vehicle sensor data revealing that drivers system- atically underestimate their short-trip behavior; and (3) a pilot intervention in the Netherlands testing the e”ectiveness of personalised smartphone feedback which increased awareness but did not result in significant behavioral change. The cumulative evidence highlights three key findings. Firstly, short car trips are deeply ingrained in everyday mobility routines. Secondly, habitual behavior can lead to biased self- perceptions that limit the e”ectiveness of traditional policy instruments. Thirdly, while feedback can raise awareness, it requires structural, motivational and contextual support to enable be- havioral change. From a methodological perspective, this work illustrates the benefits of using a mixed-methods approach in mobility research by combining large-scale sensor data, survey research and behavioral interventions. Theoretically, it confirms the habitual nature of car use and highlights a discrepancy between awareness and action. In practice, it provides policy- relevant insights into reducing short car trips by integrating behavioral insights with urban design, regulations, and alternative mobility solutions. Overall, the findings emphasise that reducing short-distance car use requires more than ra- tional choice; it also demands consideration of habits and perception. Therefore, sustainable mobility transitions will depend on combining behavioral approaches with structural transform- ation.