Segment A portion, or subset, of a larger unit, generally in reference to population groups. For the Census Bureau, there are three specific uses of the term: (1) a type of administrative subdivision found on an American Indian reservation; (2) a portion of a linear feature, generally occurring between the intersections with two other linear features, but also between two points used to define the shape of a feature; and (3) the part of a census block (or ED in earlier decennial censuses) used as the sampling unit for the Census Bureau’s sample surveys in areas without city-style addresses geocoded to the census block level. See also American Indian subreservation area, GBF/DIME-File, linear feature, TIGER data base, TIGER System.
Serpentine numbering The method or pattern of assigning numbers on a map in a snake-like, winding manner, with the intent of having each number located next to the other in the sequence.
Service industries (census) See economic census.
Short form The decennial census questionnaire, sent to approximately five of six households for the 1980 and 1990 censuses, that contains population questions related to household relationship, sex, race, age, marital status, and Hispanic origin as well as housing questions about the number of units in each structure, the number of rooms per unit, tenure, and value. The questions contained on the short form also are asked, along with additional questions, on the long form. See also long form, 100-percent data, sample data.
SMA See standard metropolitan area.
Small-area data The Census Bureau uses this term to refer to census statistics tabulated at the census block, block group, and census tract/BNA level. (Many people also would include in this category, data for places and MCDs having fewer than 5,000 inhabitants.)
SMSA See standard metropolitan statistical area.
