The success of campaigns and policies directed towards reducing private car use is, for the most part, dependent upon understanding the psychological factors that influence an individual's travel mode decisions. In general, however, interventions to reduce car use have been based on informal conceptualisations, designed without elicitation research, and directed primarily at providing information about the negative consequences of car use. This information is usually not sufficient to change behaviour. In fact, whether people choose to drive or take public transport has been found to be only weakly related to their knowledge about the environmentally damaging effects of extensive private car use. Intervention strategies based on empirically validated theories are more promising, though in relation to the choice of travel mode, there is a lack of research that utilise such approaches.
The objectives are to:
- Identify relevant attitudinal factors upon which transport decisions are made;
- Develop a measurement tool for quantifying and weighting the attitudinal factors in terms of their relative impact on transport decisions;
- Identify variation in the factors that impact on different population sub-group's transport decisions;
- Produce an empirically standardised tool and related normative database for the ongoing measurement of attitudes and the evaluation of policy impact at local and national levels.
The theory of planned behaviour has provided one of the most influential contributions to the field of attitude measurement and the prediction of behaviour. The application of this theory to travel choice will provide an empirically grounded model to help understand the reasons why drivers currently prefer to use their car rather than using public transport.