U.S. Department of Commerce U.S. Census Bureau Geography Division, 1996, TIGER/Line Files, 1995: TIGER/Line Files Each file cotnains a version code that uniquely identifies each specific release of a version of the TIGER/Line files. The version code for the 1995 TIGER/Line files is 0024., U.S. Department of Commerce U.S. Census Bureau Geography Division, Washington, DC.
Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000458. Longitudes are given to the nearest 0.000458. Latitude and longitude values are specified in Decimal degrees.
In order for others to use the information in the Census TIGER database in a geographic information system (GIS) or for other geographic applications, the Census Bureau releases to the public extracts of the database in the form of TIGER/Line files. Various versions of the TIGER/Line files have been released on an irregular schedule; previous versions include the 1990 Census TIGER/Line files, the 1992 TIGER/Line files, and the 1994 TIGER/Line files. The 1995 TIGER/Line files were originally produced to support Phase I of the Census 2000 Redistricting Data Program.
U.S. Department of Commerce U.S. Census Bureau Geography Division, Unpublished material, Census TIGER database.
Data sources used in this process:
Accurate against Federal Information Processing Standards (FIPS), FIPS Publication 6-4, and FIPS-55 at the 100% level for the codes and base names. The remaining attribute information has been examined but has not been fully tested for accuracy.
The information present in these files is provided for the purposes of statistical analysis and census operations only. Coordinates in the TIGER/Line files have six implied decimal places, but the positional accuracy of these coordinates is not as great as the six decimal places suggest. The positional accuracy varies with the source materials used, but generally the information is no better than the established National Map Accuracy standards for 1:100,000-scale maps from the U.S. Geological Survey (USGS); thus it is NOT suitable for high- precision measurement applications such as engineering problems, property transfers, or other uses that might require highly accurate measurements of the earth's surface. The USGS 1:100,000- scale maps meet national map accuracy standards and use coordinates defined by the North American Datum, 1983. For the contiguous 48 States, the cartographic fidelity of most of the 1995 TIGER/Line files, in areas outside the 1980 census Geographic Base File/Dual Independent Map Encoding (GBF/DIME) file coverage and selected other large metropolitan areas, compare favorably with the USGS 1:100,000-scale maps. The Census Bureau cannot specify the accuracy of features inside of what was the 1980 GBF/DIME-Files coverage or selected metropolitan areas. The Census Bureau added updates to the TIGER/Line files that enumerators annotated on map sheets prepared from the Census TIGER database as they attempted to traverse every street feature shown on the 1990 census map sheets; the Census Bureau also made other corrections from updated map sheets supplied by local participants for Census Bureau programs. The locational accuracy of these updates is of unknown quality. In addition to the Federal, State, and local sources, portions of the files may contain information obtained in part from maps and other materials prepared by private companies. Despite the fact that TIGER/Line data positional accuracy is not as high as the coordinates values imply, the six-decimal place precision is useful when producing maps. The precision allows features that are next to each other on the ground to be placed in the correct position, on the map, relative to each other, without overlap.
Data completeness of the TIGER/Line files reflects the contents of the Census TIGER database at the time the TIGER/Line files (1995 version) were created.
The feature network of lines (as represented by Record Types 1 and 2) is complete for census purposes. Spatial objects in TIGER/Line belong to the "Geometry and Topology"(GT) class of objects in the "Spatial Data Transfer Standard" (SDTS) FIPS Publication 173 and are topologically valid. Node/geometry and topology (GT)-polygon/chain relationships are collected or generated to satisfy topological edit requirements. These requirements include: * Complete chains must begin and end at nodes. * Complete chains must connect to each other at nodes. * Complete chains do not extend through nodes. * Left and right GT-polygons are defined for each complete chain element and are consistent throughout the extract process. * The chains representing the limits of the file are free of gaps. The Census Bureau performed automated tests to ensure logical consistency and limits of files. All polygons are tested for closure. Some polygons in the TIGER/Line files may be so small that the polygon internal point has been manually placed on a node that defines the polygon perimeter. These small polygons have been detected, and corrections will be incorporated in the Census TIGER database in the future. The Census Bureau uses its internally developed Geographic Update System to enhance and modify spatial and attribute data in the Census TIGER database. Standard geographic codes, such as FIPS codes for states, counties, municipalities, and places, are used when encoding spatial entities. The Census Bureau performed spatial data tests for logical consistency of the codes during the compilation of the original Census TIGER database files. Most of the codes themselves were provided to the Census Bureau by the USGS, the agency responsible for maintaining FIPS 55. Feature attribute information has been examined but has not been fully tested for consistency.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints:
- None. Acknowledgment of the U.S. Census Bureau would be appreciated for products derived from these files. TIGER, TIGER/Line, and Census TIGER are trademarks of the U.S. Census Bureau.
(301) 763-1128 (voice)
(301) 457-4710 (FAX)
geo.tiger@census.gov
1995 TIGER/Line Files
No warranty, expressed or implied is made and no liability is assumed by the U.S. Government in general or the U.S. Census Bureau in specific as to the positional or attribute accuracy of the data. The act of distribution shall not constitute any such warranty and no responsibility is assumed by the U.S. Government in the use of these files. The boundary information in the TIGER/Line files are for statistical data collection and tabulation purposes only; their depiction and designation for statistical purposes does not constitute a determination of jurisdictional authority or rights of ownership or entitlement.
Data format: | TGRLN (compressed) |
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Network links: |
www.census.gov/geo/www/tiger |
None. This version of the TIGER/Line files has been superseded by later versions and is no longer available from the Census Bureau. The latest version of the TIGER/Line files may be accesses without charge online. See <http://www.census.gov/geo/www/tiger>. The 1995 TIGER/Line files may still be available in some Federal Depository Libraries.
To obtain more information about ordering TIGER/Line files visit <http://www.census.gov/geo/www/tiger>.
The 1995 TIGER/Line files contain geographic data only and do not include display or mapping software or statistical data. For information on how to use the TIGER/Line data with a specific software package users should contact the company that produced the software. A list of some vendors who have developed software capable of processing TIGER/Line files can be found by visiting <http://www.census.gov/geo/www/tiger>. The Census Bureau provides TIGER/Line files in ASCII text format only. Users are responsible for converting or translating the files into a format used by their specific software package.
(301) 763-1128 (voice)
geo.tiger@census.gov