Slope, aspect the term slope addresses the steepness of an area while aspect is related to the direction in which an area is oriented. The calculation of the angle of the topographic slope is generally based on a digital frame file with its grid of polygons and the classification of that surface of slope variation into ranges. A listing of spatial autocorrelation statistics for increasing orders of contiguity is referred to as a spatial correlogram. Spatial stochastic process formalizes the way in which spatial association is generated or generally expresses how observations at each location depend on values at neighbouring locations, that is, on the spatial lags. Suitability analysis a variant of spatial analysis in which GIS map layers are integrated to form a composite choropleth map for decision making.
Examples are maps derived from weighted intersection overlay and weighted multidimensional scaling.
Theissen Polygons See Voronoi . Topography the collective features on the surface of the earth, including relief, hydrography and cultural features. Topographic maps of the U.S. are produced by the U.S. Geological Survey for GIS use. In public health, topographic maps can reveal disease associations with elevation, surface water, wind direction, solar exposure, time and other factors. Topology the relationship between points, lines, and geometric forms that remain consistent throughout spatial operations in a digital mapping environment.