PhD defence H. (Hannah) Gorges

Below is a brief summary of the dissertation:

This PhD thesis examines why people continue to use cars for very short trips, despite the fact that walking, cycling or using public transport would often be a possible option. These short trips are important because they are particularly inefficient and unnecessarily contribute to emissions, congestion and pressure on urban space. Using large-scale vehicle sensor data, I demonstrate that short car trips form a stable and widespread part of everyday mobility, suggesting that they are often undertaken out of habit rather than by conscious choice.

A second key finding is that many drivers are not fully aware of their own behaviour. When I compared self-assessments with real mobility data, people consistently underestimated how often they used the car, particularly for short trips. This helps to explain why changing behaviour is so difficult: if people do not recognise the pattern, they are unlikely to question and change it.

Finally, I tested whether personalised feedback delivered via a smartphone app could encourage behavioural change. The results showed that, while feedback might increase awareness, it did not lead to measurable reductions in short car trips on its own. Overall, this thesis demonstrates that reducing car dependency is not solely dependent on infrastructure or distance. It also requires a better understanding of routines, perceptions, and timing. In order to make urban mobility more sustainable, behavioural interventions must complement transport and planning policy.