Glossary

Sample data
Population and housing information collected from the census long form for a one in six sample of households in the United States and Puerto Rico, and on a continuous basis for selected areas in the American Community Survey.

Related terms: American Community Survey (ACS), Census (decennial), Long form

Sampling error
Errors that occur because only part of the population is directly contacted. With any sample, differences are likely to exist between the characteristics of the sampled population and the larger group from which the sample was chosen. Sampling error, unlike nonsampling error, is measurable.

School District
Geographic entities within which state, county, or local officials provide public educational services for the area’s residents. The boundaries and names are provided by state officials.

School enrollment
Enrollment in regular school, either public or private, which includes nursery school, kindergarten, elementary school, and schooling which leads to a high school diploma or college degree.

Related terms: Educational attainment, Grade in which enrolled

Sector (economic)
In the 1997 economic census data are classified into 20 NAICS sectors, using a 2 digit code. These sectors are subdivided into 96 sub-sectors, using a 3 digit code.

Related term: North American Industry Classification System (NAICS)

Sex
An individual's gender classification - male or female.

Sex ratio
A measure derived by dividing the total number of males by the total number of females, and then multiplying by 100.

Short form
The decennial census questionnaire, sent to approximately five of six households for the 1980, 1990, and 2000 censuses. For Census 2000, the questionnaire asked population questions related to household relationship, sex, race, age and Hispanic or Latino origin and housing questions related to tenure, occupancy, and vacancy status. The 1990 short form contained a question on marital status. The questions contained on the short form also are asked on the long form, along with additional questions.

Related terms: Census (decennial), Long form

Spanish/Hispanic/Latino
A self-designated classification for people whose origins are from Spain, the Spanish-speaking countries of Central or South America, the Caribbean, or those identifying themselves generally as Spanish, Spanish-American, etc. Origin can be viewed as ancestry, nationality, or country of birth of the person or person’s parents or ancestors prior to their arrival in the United States.

Spanish/Hispanic/Latino people may be of any race.

Related terms: Ancestry, Race

Spouse
A person legally married to another person.

Standard deviation
A measure which shows the average variability in population from the mean. It is defined as the square root of the variance.

Standard error (ACS)
The standard error is a measure of the deviation of a sample estimate from the average of all possible samples.

Related terms: American Community Survey (ACS), Confidence interval (ACS), Estimates (American Community Survey)

Standard Industrial Classification (SIC)
Industry classification system that was used in Economic Censuses prior to 1997. This system identifies establishments by the principal activity in which they are engaged. SIC has been replaced by North American Industry Classification System (NAICS) in the 1997 Economic Census.

Related terms: Economic census, North American Industry Classification System (NAICS)

State and equivalent entity
The primary legal subdivision of the United States. The District of Columbia, Puerto Rico and the Island Areas (the U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands) are each treated as the statistical equivalent of a state for census purposes.

State data center (SDC)
A state agency or university facility identified by the governor of each state and state equivalent to participate in the Census Bureau’s cooperative network for the dissemination of census data. A SDC also may provide demographic data to local agencies participating in our statistical areas.

State Designated American Indian Statistical Area (SDAISA)
A statistical entity for state recognized American Indian tribes that do not have a state recognized reservation. SDAISAs are identified and delineated for the Census Bureau by a designated state official. They generally encompass a compact and contiguous area that contains a concentration of individuals who identify with a state recognized American Indian tribe and in which there is structured or organized tribal activity. New for the 2000 Census.

State legislative district (SLD)
An area from which members are elected to state legislatures. The SLDs embody the upper (senate) and lower (house) chambers of the state legislature. (Nebraska has a unicameral legislature that is represented as an upper chamber legislative entity.)

State Senate District not defined- The name assigned to an area of unpopulated coastal water within a state that belongs to no state senate district.

State House District not defined- The name assigned to an area of unpopulated coastal water within a state that belongs to no state house district.

Stepfamily
A "married couple" family in which there is at least one stepchild of the householder present. If the child has been adopted by the householder, that child is classified as an adopted child and the family is not classified as a stepfamily, unless another non-adopted stepchild is present.

Related terms: Adopted child, Family

Subbarrio
The primary legal subdivision of the barrios-pueblo and some barrios in Puerto Rico. There is no United States equivalent.

Related terms: Barrio, Barrio-Pueblo

Subfamily
A married couple (with or without children) or a single parent with one or more never-married children under the age of 18, residing with and related to the householder, but not including the householder or the householder's spouse.

When grown children move back to the parental home with their own children or spouse, they are considered a subfamily.

Related terms: Family, Householder

Sub-sector (economic)
In the 1997 economic census data are classified into 96 sub-sectors using a 3 digit NAICS code.

Related term: North American Industry Classification System (NAICS)

Summary file (SF)
Statistics for a large number of geographic areas that are designed to show great subject matter detail presented in tabular form. There are four main summary files produced from the data collected during Census 2000.

See the individual definitions for Summary Files 1, 2, 3, and 4 for a more in-depth explanation of each.

Related term: Census (decennial)

Summary File 1 (SF 1)
This file presents 100-percent population and housing figures for the total population, for 63 race categories, and for many other race and Hispanic or Latino categories. This includes age, sex, households, household relationship, housing units, and tenure (whether the residence is owned or rented). Also included are selected characteristics for a limited number of race and Hispanic or Latino categories. The data are available for the U.S., regions, divisions, states, counties, county subdivisions, places, census tracts, block groups, blocks, metropolitan areas, American Indian and Alaska Native areas, tribal subdivisions, Hawaiian home lands, congressional districts, and ZIP Code Tabulation Areas. Data are available down to the block level for many tabulations, but only to the census-tract level for others. Available on CD-ROM, DVD, and American FactFinder.

The Census 2000 Summary File 1 data are released in three stages. Individual state files and two national files are released. The state-level data are released first, followed by the Advance National File, which covers the same data subjects, but includes national level summary data such as ZCTAs, whole metropolitan areas, whole American Indian areas, etc. The Final National File contains the same data subjects and geographic areas as the Advance National File, but adds the first available urban/rural and urbanized area data. For the most current release dates for these files, see the "Census 2000 Release Schedule" link on the AFF Main Page.
Planned release dates:
(States): June-September 2001
(Advance National File): November-December 2001
(Final National File): May-June 2002

Related term: Census (decennial)

Summary File 2 (SF 2)
This file presents data similar to the information included in Summary File 1. These data are shown down to the census tract level for 250 race, Hispanic or Latino, and American Indian and Alaska Native tribe categories. For data to be shown in SF 2, a population category must meet a population size threshold of 100 or more people of that specific population category in a specific geographic area. Available on CD-ROM, DVD, and American FactFinder.

Related term: Census (decennial)

Summary File 3 (SF 3)
This file presents data on the population and housing long form subjects such as income and education. It includes population totals for ancestry groups. It also includes selected characteristics for a limited number of race and Hispanic or Latino categories. The data are available for the U.S., regions, divisions, states, counties, county subdivisions, places, census tracts, block groups, metropolitan areas, American Indian and Alaska Native areas, tribal subdivisions, Hawaiian home lands, congressional districts, and Zip Code Tabulation Areas. Available on CD-ROM, DVD, and American FactFinder.

Related terms: Census (decennial), Long form

Summary File 4 (SF 4)
This file presents data similar to the information included in Summary File 3. These data are shown down to the census tract level for 336 race, Hispanic or Latino, American Indian and Alaska Native tribe, and ancestry categories. For data to be shown in SF 4, there must be at least 50 unweighted sample cases of a specific population category in a specific geographic area. In addition, the data for the specific population category for the specific geographic area must also have been available in Summary File 2. Available on CD-ROM, DVD, and American FactFinder.

Related terms: Census (decennial), Long form

Summary table
A collection of one or more data elements that are classified into some logical structure either as dimensions or data points.

Summary Tape Files 1-4 (STFs 1-4)
Summary tape files are products of the 1990 Census of Population and Housing. They are summary tabulations of 100-percent and sample population and housing data available for public use on computer tape and CD-ROM. Summary Tape Files 1 and 3 also are available through American FactFinder.

Related terms: 100-Percent data, Products