Showing papers by "Barry Boots published in 2000"

Global and local spatial autocorrelation in bounded regular tessellations

Abstract: This paper systematically investigates spatially autocorrelated patterns and the behaviour of their associated test statistic Moran's I in three bounded regular tessellations. These regular tessellations consist of triangles, squares, and hexagons, each of increasing size (n=64; 256; 1024). These tesselations can be downloaded at http://geo-www.sbs.ohio-state.edu/faculty/tiefelsdorf/regspastruc/ in several GIS formats. The selection of squares is particularly motivated by their use in raster based GIS and remote sensing. In contrast, because of topological correspondences, the hexagons serve as excellent proxy tessellations for empirical maps in vector based GIS. For all three tessellations, the distributional characteristics and the feasibility of the normal approximation are examined for global Moran's I, Moran's I(k) associated with higher order spatial lags, and local Moran's Ii. A set of eigenvectors can be generated for each tessellation and their spatial patterns can be mapped. These eigenvectors can be used as proxy variables to overcome spatial autocorrelation in regression models. The particularities and similarities in the spatial patterns of these eigenvectors are discussed. The results indicate that [i] the normal approximation for Moran's I is not always feasible; [ii] the three tessellations induce different distributional characteristics of Moran's I, and [iii] different spatial patterns of eigenvectors are associated with the three tessellations.

Using GIS to promote spatial analysis

Abstract: This paper examines why GIS has made little contribution to the dissemination of spatial analysis procedures. In the future, it is anticipated that GIS is more likely to embrace procedures which are exploratory and local and which are capable of performing multiple roles. To facilitate this, there is a need to develop more interdisciplinary interaction, new texts, and integrated software.