A dynamic discrete-choice model for movement flows

Consider the case when individual units, call them actors, are affiliated with at most one, higher organisational unit but these affiliations change over time. This could be the case of people working for organisations or people living in neighbourhoods. We draw on dynamic models for social networks to propose an actor-oriented model for how these affiliations change over time. These models specifically take into account constraints of the system and allow for the system to be observed at discrete time-points. Constraints stem from the fact that not everybody can get the same job or live in the same neighbourhood, something which induces dependencies among the decisions. The model encompasses two modelling components: a model for determining the termination of an affiliation; and a discrete-choice model for determining the new affiliation. For estimation we employ a Bayesian data-augmentation algorithm, that augments the observed states with unobserved sequences of transitions. We apply the proposed methods to a data set of house-moves in Stockholm and illustrate how we may infer the mechanisms that sustain and perpetuate segregation on the housing market.