National Historical Geographic Information System

University Of Minnesota-Twin Cities, Minneapolis MN

Investigators

Abstract

Small-area census data are the primary source for studying such critical issues in social science research as suburbanization, the decline and rebirth of central cities, residential segregation, immigrant settlement patterns, rural depopulation, agricultural consolidation and population shifts from the rust belt to the sunbelt. These issues cry out for chronological analysis, but because historical small-area data are inaccessible, most studies are static. Researchers who address change over time in spatial processes must either confine their analyses to local areas because broader studies are simply too expensive or they must adopt large units of analysis, such as states and metropolitan areas, which preclude the nuanced detail needed for full understanding. This Social, Behavioral, and Economic Science Infrastructure award will support the work to make the census accessible to researchers within the framework of a comprehensive National Historical Geographic Information System (NHGIS). A multidisciplinary research team will bring together approximately 670 gigabytes of data covering the period 1790 through 2000 that currently are scattered across dozens of archives and stored in incompatible formats on different media. This project will consist of three major components. (1) The data and documentation component will gather all extant machine-readable census summary data, fill holes in the surviving machine-readable data through data entry of paper census tabulations, harmonize the formats and documentation of all files, and produce standardized electronic documentation according to the recently developed Data Documentation Initiative (DDI) specification. (2) The mapping component will create consistent historical electronic boundary files for tracts, minor civil divisions, Counties, and larger geographic units. (3) The data-access component will create a powerful but user-friendly, Web-based browser and extraction system based on the new DDI metadata standard. The system will provide public access free of charge to both documentation and data and will present results in the form of tables or maps. The census constitutes a fundamental underpinning of social science and policy research. It also represents an exceptional untapped resource for secondary and higher education in the social science, statistics, and history. This project will allow all users -- from high school students to research scientists -- to adopt a comparative and historical perspective. The NHGIS database will open a new range of powerful approaches to familiar problems, broadening the scope of local and regional analyses to explore variations across time and space simultaneously. The database will have even broader application when combined with other sources. The census provides basic denominators for an array of studies across the social sciences, including such diverse fields as political science, criminal justice, and epidemiology. The availability of small-area data and geographic boundary files will allow such analyses to incorporate a chronological as well as a spatial dimension. Furthermore, social scientists have become increasingly aware that individuals' life changes, choices, and attitudes are shaped not only by their own characteristics but also by the characteristics of their neighbors and communities. The NHGIS will encourage and greatly simplify the use of techniques such as multi-level analysis that draw upon such insights. These aggregate-level census data will dovetail with and complement widely used micro-level datasets, such as the Integrated Public Use Microdata Series, the American Community Survey, the Panel Study of Income Dynamics, and other specialized surveys. The NHGIS database will democratize access to the census. The database will be a resource that can be used widely for social science training, by the media, for policy research at the state and local levels, by the private sector, and in secondary education.