The application of time-geographic concepts to urban micro-process

Abstract

This thesis seeks to investigate how individual human activity patterns can be linked to provide wider insights on structure, pattern and process at higher levels of generalisation. In so doing, it seeks to advance our treatment of the concepts of accessibility and interaction in urban space. Hagerstrand's concepts of the life-line and time-space pm' m, and consequent derivations from these, have provided a means of interpreting an individual's opportunities and constrain' ts in space, while simultaneously questioning the wisdom of separating time from space in evaluating accessibility and location. Traditionally, Time Geography concentrated its efforts either on the ideographics of the individual's circumstances or on theoretical debate regarding broad movement patterns. This was largely due to a number of theoretical and methodological difficulties associated with the representation and analysis of large numbers of individual space-time paths. This research attempts to move beyond this duality to operationalise and generalise core concepts of Time Geography, using the domain of Tertiary Education as a context. It constitutes a preliminary attempt to implement core Time-Geographic concepts using tools from Geographic Information Science. It develops an extended raster data-model to operationalise these concepts, which facilitates the generation, query, aggregation and visualisation of space-time artefacts. A sample of 2,100 University students provides the dataset for model testing and development. The initial goal is to provide easier access to the insights available from Higerstrand's view of the individual, but the main aim is to develop means of dealing with aggregate phenomena, an area that traditional Time Geography developed only theoretically. It is demonstrated that in' dividull-level models can be aggregated in a variety of ways to derive a range of useful space-time artefacts. A syntax is developed which standardises key components of space-time queries, and a range of individual and aggregate queries are documented which can unambiguously answer questions relating to accessibility, presence, and absence in space. The application domain is used to test and develop key components of a methodology for the analysis of spatiotemporal phenomena, and for moving flexibly from individual to aggregate manifestations of dynamic urban (micro)-processes. The outcomes show the existence of distinct aggregate patterns of space-time presence and accessibility, related to individual timetables and constrain' ts, transportation, and the spatial distribution of agents' home locations potential activity sites. Aggregate outcomes demonstrate the complex effect of multiple individual paths in creating large-scale patterns of presence, absence and access.