An attention to location, spatial interaction, spatial structure and spatial processes lies at the heart of research in several
subdisciplines in the social sciences. Empirical studies in these fields routinely employ data for which locational attributes (the
"where") are an important source of information. Such data typically consist of one or a few crosssections of observations for either
micro-units, such as households, store sites, settlements, or for aggregate spatial units, such as electoral districts, counties, states or
even countries. Observations such as these, for which the absolute location and/or relative positioning (spatial arrangement) is taken
into account are referred to as spatial data. In the social sciences, they have been utilized in a wide range of studies, such as
archeological investigations of ancient settlement patterns (e.g., in Whitley and Clark, 1985, and Kvamme, 1990), sociological and
anthropological studies of social networks (e.g., in White et al., 1981, and Doreian et al., 1984), demographic analyses of geographical
trends in mortality and fertility (e.g., in Cook and Pocock, 1983, and Loftin and Ward, 1983), and political models of spatial patterns
in international conflict and cooperation (e.g., in O’Loughlin, 1985, and O’Loughlin and Anselin, 1991). Furthermore, in urban and
regional economics and regional science, spatial data are at the core of the field and are studied to model the spatial structure for a
range of socioeconomic variables, such as unemployment rates (Bronars and Jansen, 1987), household consumer demand (Case,
1991), and prices for gasoline (Haining, 1984) or housing (Dubin, 1992).