Activities as Generators of Spatial Interaction

Abstract

Referring back to Sect. 1.2.3, we see that the paper of Hägerstrand (1970) was pivotal in broadening the concept of the modelling of travel per se towards direct consideration of the spatial consumption of the goods and services (the ‘activities’) which generate the travel. These activities can be grouped into non-discretionary ones such as work and driving kids to school, and discretionary ones such as shopping and entertainment. This implies, for modelling, that discretionary activities must be allocated over time into the interstices separating the non-discretionary activities. It is clear that we have an interlinked process of spatial allocation of both time and money, divided into that needed to travel to and from the activities and that involved in their actual consumption. The understanding and modelling of this set of processes continues to pose problems of combinatorial complexity thirty years after the seminal paper of Hägerstrand. The essential elements of these processes and the resulting implications for modelling are now summarised, drawing extensively on Roy et al. (2001).