Turning points in car ownership over the life course: contributions from biographical interviews and panel data

There is still much to learn about why people make major changes to their personal mobility. It is challenging to identify the points in time when people make major changes in their personal mobility and the circumstances in which such changes take place and the motivations for change. Some studies have used panel data from large-scale surveys while others have conducted biographical interviews with small numbers of participants. These two approaches to research stem from very different epistemological and methodological perspectives, yet provide potentially complementary insights. This chapter provides a critical examination of the contributions from the two forms of research enquiry through reviewing examples of research on car ownership. The examples demonstrate that the traditional idea of qualitative research being used to formulate theory and quantitative research being used to test theory is apparent, but it would be more accurate to describe the two types of research as being part of an iterative process of research which contributes to accumulated knowledge in a less predictable way. We advocate that common theoretical frameworks are applied to build knowledge using both qualitative and quantitative approaches. Although purely qualitative or purely quantitative longitudinal approaches can be designed to generate evidence on processes of change and causality, it will be beneficial to adopt both approaches to build a robust evidence base. Up to this point, a systematic approach has not been taken in combining research enquiry based on panel data with enquiry based on biographical interviews. We recommend researchers engage in considering the epistemological, methodological and analytical issues involved in combining the two forms of enquiry, as there is the prospect of making major strides in the understanding of personal mobility over the life course.