Potential Path Areas and Activity Spaces in Application: A Review

The potential path area (PPA) and activity space (AS) concepts play a central role in the substantial amount of applied research focusing on the quantitative analysis and description of people's spatial behaviour. Given this large literature, and the surprising lack of a formal review of the research, the time is ripe for a systematic review. This paper examines how the key concepts of PPAs and ASs have evolved, how they have been applied, what issues need to be resolved, and potential areas for future research. The review begins with the main theoretical developments influencing the applied use of these methods, and continues with a categorization of the literature across three dimensions -- research domain, methods of calculation and application purpose. We find that the methods have been used not only in the core originating fields of travel behaviour and transport geography, but also in health, criminology and demography, and are growing fastest in health. The methods have been applied to a number of purposes with applications to accessibility the most common and the fastest growing. Demonstrated interest in these methods, along with the technologies and data to facilitate them, suggests a bright future for the use of PPAs and ASs in the social sciences.