DOI: 10.3886/icpsr27501.v1
title: National Neighborhood Crime Study (NNCS), 2000
title: Version 1

description: The primary purpose of the National Neighborhood Crime Study (NNCS) was to assemble tract-level crime and sociodemographic data for cities across the United States in order to permit analyses of the sources of crime for "communities" of different racial-ethnic and class composition. The NNCS also sought to examine the extent to which the causes of crime in communities are contingent on the types of geographic region, labor market, or other contextual characteristics. To fulfill these purposes, the NNCS compiled crime and sociodemographic data for census tracts in a representative sample of large United States cities for 2000. The dataset includes: (1) tract-level crime data pertaining to seven of the FBI's crime index offenses; (2) tract-level information on social disorganization, structural disadvantage, socioeconomic inequality, mortgage lending, and other control variables garnered from the 2000 United States Census of Population and Housing Summary File 3 (SF3) and other publicly available sources; (3) city-level information for the city in which the tract is located, focused on labor market structure, socioeconomic inequality, population change, and other control variables; and (4) metropolitan area data for the Metropolitan Statistical Area (MSA) or Primary Metropolitan Statistical Area (PMSA) in which the tract is located, focused on labor market structure, socioeconomic inequality, population change, and other control variables (also taken from the 2000 Census and other publicly available sources). The NNCS contains data for 9,593 census tracts in 91 cities in 64 metropolitan areas. (Please see the collection note section for additional information about variable naming.)
description: The NNCS is comprised of a sample of 9,593 census tracts that are wholly or partly inside the boundaries of large United States cities (census places) for which address-based data for seven index crimes were available. The primary goal was to explore the sources of variation in crime for communities in the United States that vary in both their racial/ethnic and economic composition. The sample is designed to represent the regional, population size, racial/ethnic composition, and poverty status of urban "neighborhoods" in the United States in 2000. The principal investigator began with a stratified (within region) random sample of cities with a population of at least 100,000 in 1999, and proceeded to request from police departments of these cities address-based crime incident data or tract-level counts of index crimes. When such data were not available for a city in the original sample, the city was replaced with an alternative place of similar size, racial/ethnic composition, and level of poverty. (See Appendix A in the codebook for an alphabetical listing of the cities that form the basis of the tract data in the NNCS.1.) The end result is data for a set of tracts in a sample of United State cities that is representative of large places in terms of the relevant dimensions noted above. Census tracts with small populations (under 300 people) or that are dominated by institutionalized populations (more than 50 percent of the population resides in group quarters) were excluded from the NNCS data set. In five cities, the police department provided offense counts for census tracts based upon 1980 or 1990 tract boundaries. For these five places, some census tracts were combined to make the census tracts for which crime and other data were available comparable with 2000 Census tracts. A list of census tracts that are combined along with the census tract identification numbers included in the NNCS data is provided in Appendix B of the codebook. Table 1 presents data on select characteristics for all large United States cities compared to the cities with tracts included in the NNCS.
description: Datasets: DS1: National Neighborhood Crime Study (NNCS), 2000
description: record abstractsVariable names with the prefix "t_" represent census tract-level variables.Variable names with the prefix "c_" represent city-level (i.e., census place) variables.Variable names with the prefix "m_" represent metropolitan-level (i.e., MSA or PMSA) variables.Variable names with no prefix represent aspects of geographic location that apply to all three levels.