Building a life-course intertemporal discrete choice model to analyze migration biographies

Individual migration mobilities over the life course have not been well understood in existing studies, and therefore ways to represent the underlying intertemporal dynamics and heterogeneities have remained unclear. To fill this research gap, this study investigates the domestic migration of people residing in the Capital Area of Japan, which has suffered from various issues caused by the over-concentration of population for several decades. Using a web-based questionnaire survey, workers aged 20–49 living in the Capital Area were requested to recall their five latest migration experiences (i.e., migration biography). A life-course intertemporal discrete choice model with cross-sectional and longitudinal heterogeneities was developed to represent individual migration destination biographies, by introducing quasi-hyperbolic utility and drawing on time preference theory. It was found that a considerable proportion of working people in the Capital Area (especially Tokyo) are from other regions of Japan. In the modeling analysis, the temporally-changing, intertwined and heterogeneous roles of place attachment, motives and altruism in migration decisions over the life course are empirically confirmed. Nonlinear influences of past, present and future utilities are further revealed, where the past utility grows more influential, and the importance of future utility diminishes over time. Policy implications of the derived findings for the development of megacities and local cities are discussed.