The National Historical Geographic Information System (NHGIS) is a new project to make a rich body of aggregate census data accessible within a Geographic Information Systems (GIS) framework for historical population research. The authors are developing a database incorporating all available aggregate census information for the United States between 1790 and 2000, including all surviving machine-readable aggregate data and new data transcribed from printed and manuscript sources. They are also creating new census-tract maps back to 1910, state and county maps back to 1790, and additional maps when feasible. Availability of high-quality boundaries for key statistical areas will permit the reconciliation of changes in census geography. Census data, documentation, and boundary files will be freely disseminated through an integrated Web-based data access and mapping system.
Bibliographical noteFunding Information:
Demographic, Economic, and Social Data: The United States, 1790-1970,’’ a data set created 30 years ago by the ICPSR with funding from the National Science Foundation (ICPSR study 0003). This data set includes the bulk of published nineteenth-and early-twentieth-century state-and county-level statistics from the censuses of population, agriculture, manufacturing, and religion. Unfortunately, the file is incomplete and is plagued by numerous data-entry errors. As part of the NHGIS project, Michael Haines, at Colgate University, is correcting the errors and augmenting the data set with additional information from published and machine-readable sources.’ To allow analysis of political change, we are also including the ICPSR county-level election return studies, which cover the period 1790 through 1990. For the period since 1950, we are supplementing the ICPSR files with machine-readable data from county data books, economic and agricultural censuses, and county business-patterns data files.
The National Historical ‘Geographic Information System (NHGIS) is designed to make the rich body of aggregate census data accessible within a Geographic Information Systems (GIS) framework for historical population research. The five-year project began in April 2001 with funding from the National Science Foundation Social Science Infrastructure Program (BCS 0094908). The goals are to gather together all surviving census data from 1790 to 2000, format them consistently, develop comprehensive standardized machine-readable documentation, create high-precision historical electronic boundary files describing census tracts and counties, and develop innovative Web-based tools for disseminating both microdata and metadata over the Internet.
- Aggregate data
- Geographic information systems (GIS)
- National historical geographic information system (NHGIS)