Suchergebnisse

Spatial tessellation is one of the most important spatial structures in geography. There are various types of spatial tessellations such as administrative units, school districts, and census tracts. Spatial tessellations are often closely related to each other; school districts are determined by, say, administrative units and land uses; electoral districts are related to administrative units, local communities, census tracts, and so forth. Such relationships among spatial tessellations have drawn the attention of geographers; to what extent is the development of a spatial tessellation affected by a set of other tessellations? To give a clue to the answer to this question, in this paper I propose three methods for analyzing a spatial tessellation in relation to a set of other tessellations: the region-based method, the boundary-based method, and the hybrid method. They are all designed for exploratory spatial analysis rather than confirmatory analysis. The methods are evaluated through an empirical study, analysis of the administrative system in Ponneri, India, in the late 18th century.

In this paper I develop an exploratory method for analyzing changes in polygon distributions. Changes are deduced from a set of polygon distributions of different times, and represented by a directed graph. Three viewpoints for representing individual changes are proposed: topology, size, and direction. They are described qualitatively, and used for exploratory analysis of spatiotemporal distribution of changes. In addition to individual changes, their sequences are analyzed through classification, visualization, and calculation of summary statistics. The method proposed is applied to the analysis of changes in market areas of a convenience-store chain in Tokyo, Japan. The empirical study reveals the spatial structure of changes in a global scale.