Collaborative Research: The National Historical Geographic Information System

从2001年到2007年，明尼苏达大学和其他机构的研究人员一直在组装国家历史地理信息系统（NCGIS）。 国家人口普查地理信息系统的设计是为了使人们能够在地理信息系统框架内获得丰富的人口普查综合数据。 项目目标是收集1790年至2000年所有幸存的普查数据，统一格式化，为这些数据编制全面的标准化机器可读文件，创建描述普查区和县的高精度历史电子边界文件，并开发创新的网络工具，用于传播统计数据，地理数据和元数据。 然而，随着项目原定目标的实现，出现了新的机会。 该更新奖将支持继续努力更新和改进NHGIS，通过升级NHGIS系统，以应对过去五年中出现的新地理标准和统计基础设施。 特别是，该项目将重新调整NHGIS边界文件，以确保与新标准兼容。 由于人口普查局正在大幅修订其TIGER/Line文件以提高准确性，NHGIS文件将重新调整，以便历史数据与新的GIS数据发布同步。 NHGIS管理人员还将在1980年至2000年的NHGIS文件中增加地理级别，以确保研究人员可以使用这些数据。 新的NHGIS地理区域将包括街区、地点、枚举区、国会区和邮政编码制表区。 NHGIS管理人员还将把美国社区调查（ACS）纳入NHGIS。 为了利用ACS提供的连续收集数据的可能性，而且数据是连续收集的，而不是在特定的普查日收集的，综合统计的参考期根据地理单元的人口规模而不同，将这些数据纳入国家人类住区地理信息系统将需要开发创新的元数据和软件。 新的活动还将提供用户支持和传播，新的地图和数据将被添加到国家人类地理信息系统的在线地图应用程序Social Explorer中，继续完善国家人类地理信息系统将使这一资源能够加快人口普查民主化进程。 该数据库正被广泛用于社会科学培训、媒体、国家和地方各级的政策研究以及私营部门。 NHGIS数据库将越来越多地用于基础社会科学研究，扩大地方和区域分析的范围，以同时探索跨时间和空间的变化。

From 2001 through 2007, researchers at the University of Minnesota and other institutions have been assembling the National Historic Geographic Information System (NCGIS). The NHGIS was designed to make the rich body of aggregate census data accessible within a GIS framework. Project goals were to gather all surviving census data from 1790 to 2000, format them consistently, develop comprehensive standardized machine-readable documentation for those data, create high-precision historical electronic boundary files describing census tracts and counties, and develop innovative web-based tools for disseminating statistical data, geographic data, and metadata. As the project's original goals were attained, however, new opportunities had presented themselves. This renewal award will support continued work to update and improve the NHGIS by upgrade the NHGIS system in response to new geographic standards and statistical infrastructure that have become available during the last five years. In particular, the project will realign NHGIS boundary files to ensure compatibility with new standards. Because the Census Bureau is substantially revising its TIGER/Line files to improve accuracy, NHGIS files will be realigned so that the historical data will be synchronized with new GIS data releases. NHGIS managers also will add geographic levels to NHGIS files for 1980 through 2000 to ensure that these data remain available to researchers. The new NHGIS geographies will include block, place, enumeration district, congressional district, and Zip Code Tabulation Areas. NHGIS managers also will incorporate the American Community Survey (ACS) into NHGIS. In order to take advantage of the continuous data-collection possibilities offered by the ACS but also data are collected continuously instead of on a specified census day and the reference period for aggregate statistics varies according to the population size of the geographic unit, incorporating these data into NHGIS will require development of innovative metadata and software. New activities also will provide user support and dissemination, and the new maps and data will be added to the NHGIS online mapping application, Social Explorer.Continued refinement of the NHGIS will permit this resource to accelerate the process of democratizing access to the census. The database is being used widely for social science training, by the media, for policy research at the state and local levels, and by the private sector. The NHGIS database will be increasingly accessible for basic social science research, broadening the scope of local and regional analyses to explore variations across time and space simultaneously.