Spatial demography

Abstract

This issue of PNAS brings together a collection of seven papers representing work in emerging areas of spatial demography, with special reference to North America. The papers have been assembled through the efforts of Susan Hanson of Clark University (Worcester, MA) and W. A. V. Clark of the University of California, Los Angeles. Although place, density, and movement have always had a part in population studies, they have not often held center stage. Demographers' prime coordinates are the two time-like coordinates of time and age. The three space-like coordinates of physical location and the many-dimensional coordinates of social location have tended to play supporting roles. Today, this situation is changing, and a host of scientific questions that intermingle geography with demography and with the whole range of the social sciences are coming to the fore. Two reasons for the expansion of spatial demography are readily apparent. One is the recent availability of finegrained spatial data linking geographic coordinates and categories to demographic, social, and economic variables, suited for analysis with the new computing tools of geographical information systems. In the United States, the Census Bureau's TIGER (Topologically Integrated Geographic Encoding and Referencing) system of the 1990s opened up opportunities that the private sector quickly augmented, and parallel developments have proceeded around the world. A second reason, in the United States, is “adversarial legalism” (1). Political decisions regarding distributional equity across jurisdictions, involving representation, public housing, discrimination, and civil rights, are propelled into the courts, creating and funding a demand for expertise in spatial analysis. A deeper reason, perhaps, is an emotional recognition that a once-rich diversity of local particularities in customs, accents, values, legends, architecture, instincts, foods, and memories is vanishing, or retreating into less visible forms. Our technological ability to analyze differences from town to town, valley to valley, …