In perpetual motion. Time-space variations in the characteristics of visitor populations and the performance of places

The last few decennia have seen a marked increase in the fragmentation of individual activity and travel patterns in time and space. As a result of an increased spatial-temporal complexity in their everyday lives and a larger action radius, individuals nowadays enjoy many new opportunities, but also face new constraints for participation in activities and travel. As a result of these developments, the activity patterns of individuals no longer coincide with the physical morphology of the city. Instead, patterns of human interaction have crystallized in many new and complex ways. The greatest change of all, however, is the shift of the conditions in time and space in which physical interactions occur. As a result of land-use deconcentration in various forms, today's urban landscape is characterized by a multiplicity of urban forms and systems ranging from monocentric to polycentric urban systems and sprawl. Accordingly, the size and composition of the population temporarily present in an area are expected to be related to this increased multiplicity. More specifically, the characteristics of these visitor populations may increasingly depend on the time-space interdependencies between each location and all other locations. From a policy perspective, the networked character of urban space and human interaction required an insight into the impact of visitor populations on the economic, environmental, and social performance of places. In addition to residential populations, visitor populations may increasingly determine this performance. For planning to be capable of taking into account these visitor populations and their impacts, it is necessary to understand the relative position of an area in terms of flows of people from different origins entering and accumulating in that area at different times of the day, without suggesting a closed network system. Planners and plans, however, still try to grasp the increased complexity in the performance of places in rather traditional conceptualizations of spatial and temporal organization. Traditional planning instruments concentrate too much on areas as static places rather than places structured around and by highly diverse (rhythms of) flows of people, goods, and information. So far, little empirical research has been conducted on the size, distribution, timing, and characteristics of visitor populations. More specifically, the implications of the growing diversity in social groups and lifestyles on people's use of places have hitherto remained largely unexplored. Furthermore, since people increasingly change the spatial orientation of their activities throughout the day, more light needed to be shed on the role of travel behaviour characteristics such as travel time and origin-destination combinations and their relationship with the presence of visitor populations. Finally, the impact of spatial environment (urban, suburban, and rural) and urban system (monocentric and polycentric) on the characteristics of visitor populations and their daily use of places was lacking. This dissertation has taken the topic of visitor populations and presented an investigation of their characteristics, their space-time dynamics during an average weekday, and their impacts on the performance of places