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Census Tracts, 1995 - California
- Identification Information
- Data Quality Information
- Spatial Data Organization Information
- Spatial Reference Information
- Entity and Attribute Information
- Distribution Information
- Metadata Reference Information
- Identification Information
- Citation
- Originator
- U.S. Department of Commerce, Bureau of the Census, Geography Division
- Publication Date
- 1996
- Title
- Census Tracts, 1995 - California
- Geospatial Data Presentation Form
- vector digital data
- Collection Title
- TIGER/Line Files, 1995
- Publication Information
- Online Linkage
- https://hgl.harvard.edu/catalog/harvard-tg95catrtpy
- Abstract
- This datalayer displays Census Tracts for the state. Census tracts are small, relatively permanent statistical subdivisions of a county or statistically equivalent entity delineated by local participants as part of the U.S. Census Bureau's Participant Statistical Areas Program. The U.S. Census Bureau delineated census tracts where no local participant existed or where a local or tribal government declined to participate. The primary purpose of census tracts is to provide a stable set of geographic units for the presentation of decennial census data. For the 1990 census, some counties had census tracts and others had block numbering areas (BNAs). Census tracts in the United States, Puerto Rico, and the Virgin Islands of the United States generally have between 1,500 and 8,000 people, with an optimum size of 4,000 people. For American Samoa, the Northern Mariana Islands, and Guam, the optimum size is 2,500 people. Counties and statistically equivalent entities with fewer than 1,500 people have a single census tract. Census tracts on American Indian reservations, off-reservation trust lands, and special places must contain a minimum of 1,000 people. (Special places include correctional institutions, military installations, college campuses, workers' dormitories, hospitals, nursing homes, and group homes.) When first delineated, census tracts are designed to be relatively homogeneous with respect to population characteristics, economic status, and living conditions. The spatial size of census tracts varies widely depending on the density of settlement, delineated with the intention of being maintained over many decades so that statistical comparisons can be made from decennial census to decennial census. However, physical changes in street patterns caused by highway construction, new developments, and so forth, may require occasional boundary revisions. In addition, census tracts occasionally are split due to population growth or combined as a result of substantial population decline. Census tracts are identified by a four-digit basic number and may have a two-digit numeric suffix; for example, 6059.02. The decimal point separating the four-digit basic tract number from the two-digit suffix is shown in the printed reports and on census maps. In computer-readable files, the decimal point is implied. Many census tracts do not have a suffix; in such cases, the suffix field is either left blank or is zero-filled. Leading zeros in a census tract number (for example, 002502) are shown only in computer-readable files. Census tract suffixes may range from .01 to .98. For the 1990 census, the .99 suffix was reserved for census tracts/block numbering areas (BNAs) that contained only crews-of-vessels population. The U.S. Census Bureau reserves the basic census tract numbers 9400 to 9499 for census tracts delineated within or to encompass American Indian reservations and off-reservation trust lands that exist in multiple states or counties (see TRIBAL CENSUS TRACTS). The number 0000 in computer-readable files identifies a census tract delineated to provide complete coverage of water area in territorial seas and the Great Lakes.
- Purpose
- These data are intended for researchers, students, and policy makers for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production. This layer will provide a basemap for layers related to socio-political analysis, statistical enumeration and analysis, or to support graphical overlays and analysis with other spatial data. More advanced user applications may focus on demographics, urban and rural land use planning, socio-economic analysis and related areas (including defining boundaries, managing assets and facilities, integrating attribute databases with geographic features, spatial analysis, and presentation output.)
- Supplemental Information
- The 1995 TIGER/Line files are an extract of selected geographic and cartographic information from the Census TIGER data base. The geographic coverage for a single TIGER/Line file is a county or statistical equivalent entity, with the coverage area based on January 1, 1995 legal boundaries. The Census TIGER database represents a seamless national file with no overlaps or gaps between parts. However, each county-based TIGER/Line file is designed to stand alone as an independent data set or the files can be combined to cover the whole nation and its territories. The 1995 TIGER/Line files consist of line segments representing physical features and governmental and statistical boundaries. The files contain information distributed over a series of record types for the spatial objects of a county. Geographic information contained in the files includes attributes such as feature identifiers/census feature class codes (CFCC) used to differentiate feature types, address ranges and ZIP Codes, codes for legal and statistical entities, latitude and longitude coordinates of linear and point features, landmark point features, area landmarks, key geographic features, and area boundaries. NOTE: Portions of this metadata file have been copied directly from Census documentation.
- Temporal Extent
- Currentness Reference
- ground condition
- Time Instant
- 1995101
- Bounding Box
- West
- -88.473227
- East
- -84.888967
- North
- 35.007882
- South
- 30.194045
- ISO Topic Category
- boundaries
- Theme Keyword
- Census
- Census districts
- Administrative divisions
- Theme Keyword Thesaurus
- LCSH
- Place Keyword
- California
- Place Keyword Thesaurus
- GNIS
- Temporal Keyword
- Access Restrictions
- None.
- Use Restrictions
- For educational, non-commercial use only. TIGER, TIGER/Line, and Census TIGER are trademarks of the Bureau of the Census. Although this data set has been developed by the U.S. Census Bureau, no warranty expressed or implied is made by the Bureau as to the accuracy of the data and related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the Bureau in the use of this data, or related materials.
- Status
- Complete
- Maintenance and Update Frequency
- Datalayers derived from TIGER/Line files are extracted from the Census TIGER data base when needed for geographic programs required to support the census and survey programs of the Census Bureau. No changes or updates will be made to the 1995 files.
- Point of Contact
- Contact Organization
- U.S. Department of Commerce, Bureau of the Census, Geography Division
- Delivery Point
- 8903 Presidential Pkwy, WP I
- Delivery Point
- Bureau of the Census
- City
- Upper Marlboro
- City
- Washington
- State
- Maryland
- State
- District of Columbia
- Postal Code
- 20772
- Postal Code
- 20233
- Country
- USA
- Country
- USA
- Contact Telephone
- 1-301-457-1128
- Contact Facsimile Telephone
- 1-301-457-4710
- Contact Electronic Mail Address
- TIGER@census.gov
- Hours of Service
- Monday through Friday 8:30 A.M. to 4:30 P.M. EST-USA
- Credit
- U.S. Department of Commerce, Bureau of the Census, Geography Division.
- Native Data Set Environment
- Microsoft Windows NT Version 4.0 (Build 1381) Service Pack 6; ESRI ArcCatalog 8.2.0.700
- Collection
- Originator
- U.S. Department of Commerce, Bureau of the Census, Geography Division
- Publication Date
- 1996
- Title
- TIGER/Line Files, 1995
- Edition
- Version (0024)
- Publication Information
- Publication Place
- Washington, DC
- Publisher
- U.S. Department of Commerce, Bureau of the Census
- Data Quality Information
- Attribute Accuracy Report
- 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.
- Logical Consistency Report
- 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 data base 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 data base. 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 data base 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.
- Completeness Report
- Data completeness of the TIGER/Line files reflects the contents of the Census TIGER data base at the time the TIGER/Line files (1995 version) were created.
- Horizontal Positional Accuracy Report
- 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 data base as they attempted to traverse every street feature shown on the 1990 census map sheets. The 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.
- Lineage
- Source
- Originator
- U.S. Department of Commerce, Bureau of the Census, Geography Division
- Publication Date
- Unpublished Material
- Title
- TIGER database
- Edition
- 1995
- Source Scale Denominator
- 100000
- Type of Source Media
- online
- Source Temporal Extent
- Time Period Information
- Single Date/Time
- Calendar Date
- 1995
- Source Currentness Reference
- Date the file was made available to create TIGER/Line File extracts.
- Contribution
- Selected geographic and cartographic information (line segments) from the Census TIGER database.
- Spatial Data Organization Information
- Direct Spatial Reference Method
- Vector
- Point and Vector Object Information
- SDTS Terms Description
- SDTS Point and Vector Object Type
- G-polygon
- Point and Vector Object Count
- 7486
- Spatial Reference Information
- Horizontal Coordinate System Definition
- Geographic
- Latitude Resolution
- 0.000000
- Longitude Resolution
- 0.000000
- Geographic Coordinate Units
- Decimal degrees
- Geodetic Model
- Horizontal Datum Name
- North American Datum of 1927
- Ellipsoid Name
- Clarke 1866
- Semi-major Axis
- 6378206.400000
- Denominator of Flattening Ratio
- 294.978698
- Vertical Coordinate System Definition
- Altitude System Definition
- Altitude Resolution
- 1.000000
- Altitude Encoding Method
- Explicit elevation coordinate included with horizontal coordinates
- Entity and Attribute Information
- Entity Type
- Entity Type Label
- Census Tracts
- Entity Type Definition
- ESRI Shapefile. Polygons represent feature areas
- Entity Type Definition Source
- ESRI; Department of Commerce, Census Bureau
- Attributes
- GIST_ID
- Internal Feature Identifier
- Definition Source
- Department of Commerce, Census Bureau
- FIPSSTCO
- FIPS State + County Code (Federal Information Processing StandardsNational Institute of Standards and Technology)
- Definition Source
- Department of Commerce, Census Bureau
- Attribute Value Accuracy Explanation
- First 2 digits comprise the unique State FIPS Code; Next 3 digits comprise the unique County FIPS code
- TRACT
- FIPS Tract Code (Federal Information Processing StandardsNational Institute of Standards and Technology)
- Definition Source
- Department of Commerce, Census Bureau
- STFID
- Unique Numeric Identifer
- Definition Source
- Department of Commerce, Census Bureau
- Attribute Value Accuracy Explanation
- Concatenation of State + County + Tract FIPS codes
- TG95CATRTPY.FID
- Internal feature number. (Sequential unique whole numbers that are automatically generated.)
- Definition Source
- ESRI
- SHAPE
- Feature geometry. (Coordinates defining the features.)
- Definition Source
- ESRI
- SHAPE.AREA
- Area of feature in square map units
- Definition Source
- Computed
- SHAPE.LEN
- Length of arc in map units
- Definition Source
- Computed
- Distribution Information
- Format Name
- Shape
- Distributor
- Harvard Geospatial Library
- Name
- Metadata Reference Information
- Metadata Date
- 20021108
- Metadata Contact
- Contact Information
- Contact Person Primary
- Contact Person
- Contact Organization
- Harvard Geospatial Library
- Contact Address
- Address
- Harvard University Library
- Address
- Office For Information Systems
- Address
- 1280 Massachusetts Avenue
- City
- Cambridge
- State or Province
- MA.
- Postal Code
- 02138
- Country
- USA
- Contact Voice Telephone
- 617-495-2417
- Contact Facsimile Telephone
- 617-496-0440
- Contact Electronic Mail Address
- hgl_ref@hulmail.harvard.edu
- Metadata Standard Name
- FGDC Content Standards for Digital Geospatial Metadata
- Metadata Standard Version
- FGDC-STD-001-1998
- Metadata Extensions
- Online Linkage
- http://www.esri.com/metadata/esriprof80.html
- Profile Name
- ESRI Metadata Profile
