National Historical Geographic Information System

小地区人口普查数据是研究社会科学研究中诸如郊区化、中心城市的衰落和再生、居住隔离、移民定居模式、农村人口减少、农业整合和人口从铁锈地带向阳光地带转移等关键问题的主要来源。 这些问题迫切需要时间顺序的分析，但由于历史的小区域数据无法访问，大多数研究都是静态的。 研究人员要解决空间过程随时间变化的问题，要么必须将分析局限于局部地区，因为更广泛的研究过于昂贵，要么必须采用大的分析单位，如州和大都市区，这就排除了充分理解所需的细微差别。 这个社会，行为和经济科学基础设施奖将支持工作，使人口普查访问的研究人员在一个全面的国家历史地理信息系统（NHGIS）的框架内。 一个多学科研究小组将汇集大约670千兆字节的数据，涵盖1790年至2000年期间，目前分散在几十个档案馆，并以不兼容的格式储存在不同的媒体上。 该项目将包括三个主要部分。 (1)数据和文件部分将收集所有现存的机读普查摘要数据，通过纸质普查表格的数据输入，填补现存机读数据的漏洞，统一所有文件的格式和文件，并根据最近制定的数据文件倡议规范，编制标准化的电子文件。 (2)制图部分将为区域、小行政区划、县和较大的地理单位创建一致的历史电子边界文件。 (3)数据存取部分将根据新的DDI元数据标准创建一个功能强大但用户友好的基于网络的浏览器和提取系统。 该系统将向公众免费提供文件和数据，并将以表格或地图的形式提供结果，普查是社会科学和政策研究的一个根本基础。 它也代表了社会科学，统计学和历史的中等和高等教育的特殊未开发资源。 该项目将使所有用户-从高中生到研究科学家-采用比较和历史的观点。 NHGIS数据库将为常见问题开辟一系列新的强有力的方法，扩大地方和区域分析的范围，同时探索跨时间和空间的变化。 该数据库与其他来源结合后将有更广泛的应用。 人口普查为一系列跨社会科学的研究提供了基本的证据，包括政治学、刑事司法和流行病学等不同领域。 小区域数据和地理边界文件的提供将使这种分析能够纳入时间和空间层面。 此外，社会科学家越来越意识到，个人的生活变化、选择和态度不仅取决于他们自己的特点，也取决于他们的邻居和社区的特点。 NHGIS将鼓励并大大简化利用这些见解的多层次分析等技术的使用。 这些总体普查数据将与广泛使用的微观数据集相吻合，并对这些数据集进行补充，如综合公共用途微观数据系列、美国社区调查、收入动态小组研究和其他专门调查。 NHGIS数据库将使人口普查民主化。 该数据库将成为一种资源，可广泛用于社会科学培训、媒体、国家和地方各级的政策研究、私营部门以及中等教育。

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.