Glossary of Terms
- Adobe Portable Document Format (PDF): A standard for electronic distribution that faithfully preserves the look and feel of the original document complete with fonts, colors, images, and layout.
- American Indian/ Alaska Native areas and Hawaiian homelands: These areas include the legal federally recognized American Indian Reservations, off-reservation trust lands entities, tribal subdivisions, Alaska Native Regional Corporations, and Hawaiian home lands. These areas also include the tribal-designated statistical areas that are defined for federally recognized tribes without a legal land base. The boundaries of federally recognized American Indian and Alaska Native areas are provided by the tribal governments. The State of Hawaii Department of Hawaiian Home Lands provides the boundaries for Hawaiian home lands. The boundaries of state-recognized American Indian reservations and state-designated American Indian statistical areas (for state-recognized tribes without a reservation) are provided by a state liaison designated by the state's governor.
- American Indian Reservation: An area with boundaries established by treaty, statute, and/or executive or court order. The reservations and their boundaries are identified for the Census Bureau by the Bureau of Indian Affairs (BIA) and State governments. They may cross the boundary of any other Census Bureau tabulation geography, including State. In data tabulations for reservations, trust lands outside the boundaries of a reservation are not included as part of the reservation.
- Attribute data: Data object closely associated with or belonging to a geographic entity.
- Census Blocks (Blocks): A geographic area bounded on all sides by visible features such as streets, roads, streams, and railroad tracks, and occasionally by invisible boundaries such as city, town, or county limits, property lines, and short imaginary extensions of a street or road. A block is usually the smallest geographic unit for which decennial census data are tabulated; when a block is split by an incorporated place or minor civil division (MCD) limit, the split portions of the block (1980 and earlier censuses) are the smallest. Approximately 10 million blocks are identified in Census 2000.
- Block Group (BGs): Block Groups are a group of co-located census blocks (see census block below) within a census tract, sharing the same first digit of their four-digit identifying numbers.
- Census: Count of the U.S. population conducted every ten years by the Census Bureau. The information in the Statewide Database reflects data collected in the 1990 census.
- Census Block: The smallest level of geography designated by Census Bureau. May approximate actual city street blocks in urban areas. In rural districts, census blocks may cover larger geographical areas to cover a more dispersed population.
- Census County Division (CCD): A statistical area, defined for a decennial census, comprising a densely settled concentration of population that is not incorporated, but resembles an incorporated place in that it can be identified with a name by local people. Each CDP should have a definite nucleus of residences, and the boundaries should include, as far as possible, all the surrounding closely settled territory identified with the place name. The boundaries, which usually coincide with visible features or the boundary of an adjacent incorporated place, have no legal status, nor are there any officials elected to serve traditional municipal functions. These areas were called "unincorporated places" prior to the 1980 census.
- Census Tract: A small, relatively permanent statistical subdivision of a metropolitan statistical area or selected non-metropolitan county, delineated for the purpose of presenting decennial census data. When census tracts are established, their boundaries were designed to have relatively homogeneous demographic characteristics and to contain between 2,500 and 8,000 inhabitants. Census tracts may be split by any subcounty geographic entity.
- City: A type of incorporated place with legally established boundaries and powers. In California, there are two kinds of cities: charter cities and general law cities. Unlike cities in many other states, both kinds of California cities have broad powers and enjoy considerable freedom in the form of government that may be established and the types of activities in which they may engage.
- Charter City: The authority provided in the state constitution to organize as a charter city is extended only to an existing city. Although general law cities now have nearly equal powers, charters are adopted by cities where special conditions create needs that cannot be adequately met by the state's general laws. An advantage of the charter form of government stems from the potential breadth of local authority that may be exercised. Since the powers of a charter city are not restricted to only those outlined in the general state municipal law, a city can adopt a charter and custom-tailor its organization and elective offices to provide for unique local conditions and needs. A charter can only be adopted or changed by a majority vote of city residents--not by a vote of the city council. Citizens can establish the terms and number of council members and impose other limitations upon their city council through a charter provision.
- County: The primary subdivision of a State (except Alaska and Louisiana). A county usually is a governmental unit with powers defined by State Law.
- Codebook: Defines the variables and codes that make-up the data.
- District: A political area used primarily for voting purposes (election or voting district).
- File Transfer Protocol (FTP): A means of moving files directly from the server to the local hard-drive.
- General Law City: A general law city operates within the parameters and guidelines of California municipal law. The advantage of a general law city is that general state laws have been subjected to judicial scrutiny and tested over time, so there is relatively little confusion about their application. City charters, by contrast, can be much more complicated and can raise many more questions about what can and cannot be done under state law.
- Geocoding: Placing a datapoint into a geographical location.
- Geographical hierarchy: A system of relationships among
geographical units wherein those geographical units are subdivided
into lower-order units that in turn may be further subdivided.
For example, States are subdivided into counties, which are
further subdivided into minor civil division or census county
divisions. Some census reports and summary tape files present
data in the following 1980 "hierarchical sequence":
Minor civil division (MCD)/census county division (CCD)
Place* or remainder of MCD/CCD
Census tract/block number area (BNA)*
Block group*/ enumeration district
* The asterisks denote geographic entities that may cross the boundaries of higher-level units; that is, a place that exists partly in one MCD and partly in another. In a hierarchical presentation, the lower-level units must fit into the specified framework; that is, a place crossing the boundary between two MCD's would be shown as two place parts sequenced separately following the appropriate MCD records.
- Graphic Interface File (GIF:) An image file format compatible with web browsers.
- Geographic Information System (GIS): Software designed to "map" political and demographic data to geographic entities.
- JPEG: Compressed image file.
- Metadata: Structured data about data. Increasingly this term refers to any data used to aid the identification, description and location of networked electronic resources. In this context there now exists a variety of metadata formats from the basic proprietary records used in global internet search services, through a continuum encompassing simple attribute/value records such as the ROADS templates used in eLib subject services, the more structured TEI and MARC formats, and at the richest level detailed formats such as CIMI and EAD, typically applied to archival material.
- Metropolitan Areas (MAs): An area defined by the Office of Management and Budget as a Federal statistical standard. An MA consists of a population nucleus with at least 50,000 people, together with adjacent communities that have a high degree of social and economic integration with that core. Metropolitan areas comprise at least one county, except in New England, where cities and towns are the basic geographic units.
- Minor Civil Divisions (MCDs)/ Census County Divisions (CCDs): MCDs are legally defined county subdivisions such as towns and townships. In 21 states where MCDs do not exist or are not adequate for reporting subcounty statistics, the census bureau, in cooperation with state officials and local data users, delineates county subdivisions known as Census County Divisions.
- Places: Incorporated places are population concentrations such as cities that have legally prescribed boundaries, powers, and functions. Other population centers without legally defined corporate limits or corporate powers; are defined by the Census Bureau in cooperation with state officials and local data users as Census-Designated Places and can be identified in Data tables by the acronym CDP following the place name.
- Precinct: A political boundary periodically redrawn by the county registrar of voters. Multiple precincts may change in every election. Registration precincts differ from voting precincts. A precinct polygon refers to the shape of a precinct.
- Reapportionment: A constitutionally mandated re-allocation of Congressional seats amongst the states. Allocation is based on population.
REG - Statement of Registration data compiled for all registered voters.
ABS - Statement of Registration data for registered voters that voted by absentee ballot. Please note that these data are not available for all counties. Some county election offices do not differentiate between poll voters and absentee voters.
POLL_VOTE - Statement of Registration data for registered voters who actually voted at their precinct polling station. Please note that these data are not available for all counties. Some county election offices do not differentiate between poll voters and absentee voters and/or some counties do not have polling places.
VOTE - Statement of Registration data for those registered voters that actually voted.
- Redistricting: A constitutionally mandated redrawing of local, state, and federal political boundaries every ten years following the U.S. census. The lines of Assembly, Senate, and Congressional Districts are redrawn to reflect changing demographics and population shifts. Local political boundaries are redistricted as well.
- Redistricting (Public Law 94-171) Summary File:
The first Census 2000 data files to be released will be the information
required for local redistricting. The data will include tabulations
by 63 race categories, cross-tabulated by "not Hispanic
or Latino" for the total population and the population 18
years and over. Detailed tabulations will present data down
to the block level, and will be available through two CD-ROM
series (state and national files). One Quick Table and Geographic
Comparison Table will be based on this redistricting file.
NOTE: The Public Law 94-171 numbers are expected to reflect corrections for possible overcounts and undercounts using measurements from the Accuracy and Coverage Evaluation survey. To fulfill the requirements of Public Law 105- 119 (enacted in 1997), the Census Bureau also must make publicly available a second version of these data that does not include the statistical corrections for overcounts and undercounts measurements in the Accuracy and Coverage Evaluation. Planned Release date: March 2000
Summary File 1 (SF 1)- Presents counts and basic cross-tabulations on information collected from all people and housing units. This information includes age, sex, race, Hispanic or Latino origin, household relationship, and whether the residence is owned or rented. Data will be available down to the block level for many tabulations, but only to the census-tract level for others. Summaries will also be included for other geographic areas such as ZCTAs and Congressional Districts.
Related products include Demographic Profiles that will give a snapshot of the geographic area; Quick Tables; Geographic Comparison Tables, and the first of the printed report series (See below). Planned Release date: June 2001-June 2002
Summary File 2 (SF 2)- Will also contain 100-percent population and housing characteristics, but the tables in this file will be iterated for a selected list of detailed race and Hispanic- or Latino-origin groups, as well as American Indian and Alaska Native tribes. For this file, the lowest level of geography will be the census tract, and there will be a population-size threshold before information is shown for a particular group. Various Quick Tables and Geographic Comparison Tables will be derived from Summary File 2. Planned release date: October 2001-July 2002
Summary File 3 (SF 3)- Will be the first release of the information collected on a sample basis. Data will be provided down to the block group for many tabulations but only down to the census tract for others. SF 3 will also include data by ZIP Code Tabulation Area and Congressional District. Related products include three-page profile report, various Quick Tables, and Geographic Comparison Tables, and a printed report series, developed from the sample data. Planned Release date: August-December 2002
Summary File 4 (SF 4)- Will include tabulations of the population and housing data collected from a sample of the population. Just as in Summary File 2, the tables on SF 4 will be iterated for a selected list of race and Hispanic- or Latino-origin groups, for American Indian and Alaska Native tribes, as well as for ancestry groups. Various Quick Tables and Geographic Comparison Tables will be derived from Summary File 4. Planned release date: December 2002-March 2003
- Registrar of Voters: A county-level government agency that maintains voting registration information and releases voting results by precinct.
- Shape file: A geographic data format created by ESRI, which consists of three different files: SHP, SHX, DBF. We distribute geographical information via shape files.
- Summary File: (see Redistricting Summary File).
- STF 3 (Standard Tape File 3): Data released at block group level by the Census Bureau. Contains detailed information on the demographics, income, employment, and family life of the residents of a given block group.
- Statement of Vote(SOV): Election data collected by the Registrars of Voters in the individual counties. The Statement of the Vote is reported on the Election Precinct level.
- Statement of Registration(SOR): Registration data compiled by the Registrars of Voters. The SOR includes party identification among other variables.
- Topographically Integrated Geographically Encrypted Reference (TIGER): The census geography used in the Statewide Database for geocoding is based on the TIGER file.
- Variable: an alphanumeric code that describes a piece of data. Defined in the codebook.
- Voting Districts: Voting districts represent areas created for the purpose of conducting elections. They include election districts, precincts, wards, polling areas, and other types of electoral units submitted to the Census Bureau by states participating in the Redistricting Data Program.