The Census Bureau has a master glossary of definitions covering all topics, censuses, surveys, and programs. Some poverty terms may be linked to in the Glossary, while more specific concepts are defined on the page below.
As explained by a National Academy of Sciences panel, "Absolute thresholds are fixed at a point in time and updated solely for price changes.... In contrast, relative thresholds, as commonly defined, are developed by reference to the actual expenditures (or income) of the population." See Citro and Michael, eds., Measuring Poverty: A New Approach (National Academy Press, 1995), page 31, "Types of Poverty Thresholds."
Absolute thresholds are based on a fixed set of goods that are considered necessary for survival, regardless of time or place. Year to year, the only thing that changes in the absolute threshold is the price of this set of goods. Relative thresholds are based on a set of goods that people need for survival in a particular year, and may change over time. Year to year, both the set of goods and the prices of those goods change in the threshold.
Percent of people who were in poverty in a calendar year. Annual poverty rates from the Current Population Survey and the decennial census long form are based on income reported as an annual figure. In the Survey of Income and Program Participation (SIPP), income is reported monthly. Therefore, in the SIPP, annual poverty rates are calculated using the sum of family income over the year divided by the sum of poverty thresholds that can change from month to month if one's family composition changes.
Average percent of people in poverty per month for a given year of a longitudinal survey panel. See also longitudinal survey data.
Percent of people in poverty every month for the duration of a longitudinal survey panel (typically 3 to 4 years). See also longitudinal survey data.
Data from a survey in which a new group of respondents is sampled for each interview, as opposed to following the same group of respondents over time. The Current Population Survey Annual Social and Economic Supplement (CPS ASEC), the American Community Survey (ACS), and the decennial census long form are cross-sectional surveys. See also longitudinal survey data.
Percent of people who were not in poverty during the first year of a longitudinal survey, but were in poverty in a subsequent year. Based on an annual poverty measure. See also longitudinal survey data.
Percent of people who were poor in 2 or more consecutive months in a given time period. Episodic poverty can only be calculated using monthly longitudinal survey data. See also longitudinal survey data.
The numerical relationship by which poverty thresholds vary for families of different sizes and compositions.
According to the Department of Health and Human Services, "The poverty guidelines are sometimes loosely referred to as the 'federal poverty level' (FPL), but that phrase is ambiguous and should be avoided, especially in situations (e.g., legislative or administrative) where precision is important." [//aspe.hhs.gov/poverty/05poverty.shtml, last accessed March 24, 2016.] See also poverty guidelines.
Group Quarters (GQ) are places where people live or stay, in a group living arrangement, which is owned or managed by an entity or organization providing housing and/or services for the residents. This is not a typical household-type living arrangement. Services may include custodial or medical care as well as other types of assistance, and residency is commonly restricted to those receiving these services. People living in group quarters are usually not related to each other.
Group quarters include such places as college residence halls, residential treatment centers, skilled nursing facilities, group homes, military barracks, correctional facilities, and workers’ dormitories.
Group quarters are categorized into two groups, institutional and non-institutional.
Institutional Group Quarters: Includes facilities for people under formally authorized, supervised care or custody at the time of interview, such as correctional facilities, nursing facilities, in-patient hospice facilities, mental (psychiatric) hospitals, group homes for juveniles, and residential treatment centers for juveniles.
Non-institutional Group Quarters: Includes facilities such as college/university housing, military barracks, residential treatment facilities for adults, group living quarters, and mission or job corps centers, housing shelters, and religious group quarters.
Income deficit is the amount, in dollars, that the income of a family in poverty (or unrelated individual) falls below its poverty threshold. If family income is negative, the deficit is equal to the threshold.
Income surplus is the amount, in dollars, between the income of a family or unrelated individual above the poverty level and its poverty threshold.
Data from a survey in which the same respondents are interviewed multiple times, using the same set of questions, over a period of time (a panel). The Survey of Income and Program Participation (SIPP) is a longitudinal survey. While cross-sectional data have been compared to "snapshots" in that differences between two cross-sectional estimates are based on two different samples of people, longitudinal data instead allow the analyst to observe how the status of the same group of people changes over time--for instance, by observing the average number of months a person falls below the poverty level, or by observing the demographic characteristics of people who enter and leave poverty. In that sense, longitudinal data have been compared to "videos." See also cross-sectional data.
The poverty rate in a given month. Monthly poverty thresholds are based on the appropriate annual threshold (given the monthly family composition) divided by 12, while income is based on monthly family income.
The National Research Council's Panel on Poverty and Family Assistance: Concepts, Information Needs, and Measurement Methods. The panel was composed of a group of scholars appointed by the National Research Council who co-authored a publication in 1995, Measuring Poverty: A New Approach (National Academy Press, 1995), that recommended alternative methods for measuring poverty. The Census Bureau has conducted research to refine some of the panel's measurement methods and to examine how its recommendations would affect the number in poverty and the poverty rate.
Poverty areas are census tracts or block numbering areas (BNA's) where at least 20 percent of residents were below the poverty level.
The poverty guidelines are a simplification of the poverty thresholds issued each year by the Department of Health and Human Services (HHS) for administrative purposes — e.g., determining financial eligibility for certain federal programs. These guidelines vary from the poverty thresholds, which are calculated by the Census Bureau and used for statistical purposes, namely measuring the official poverty rate.
The American Community Survey collects data on a rolling basis every month throughout the year, and therefore measures poverty in the previous 12 months instead of the previous calendar year.
The percentage of people (or families) who are in poverty.
Measured using monthly panel data from a longitudinal survey (excluding spells underway in the first interview month of the panel). Minimum spell length is defined as 2 months and Multiple spells are separated by 2 or more months of not being in poverty.
The dollar amount the Census Bureau uses to determine a family's or person's poverty status.
Persons for whom the Census Bureau can determine poverty status (either "in poverty" or "not in poverty"). For some persons, such as unrelated individuals under age 15, poverty status is not defined. Since Census Bureau surveys typically ask income questions to persons age 15 or older, if a child under age 15 is not related by birth, marriage, or adoption to a reference person within the household, we do not know the child's income and therefore cannot determine his or her poverty status. For the decennial censuses and the American Community Survey, poverty status is also undefined for people living in college dormitories and in institutional group quarters. People whose poverty status is undefined are excluded from Census Bureau poverty tabulations. Thus, the total population in poverty tables--the poverty universe--is slightly smaller than the overall population. See also, unrelated individuals, group quarters.
People and families are classified as being in poverty if their income is less than their poverty threshold. If their income is less than half their poverty threshold, they are below 50% of poverty; less than the threshold itself, they are in poverty (below 100% of poverty); less than 1.25 times the threshold, below 125% of poverty, and so on.
The Small Area Income and Poverty Estimates (SAIPE) program produces single-year model based estimates of income and poverty for states and counties, and population and poverty estimates for school districts. The estimates are provided for the administration of federal programs and the allocation of federal funds to local jurisdictions.
Unrelated individuals are people of any age who are not living with any other family members. When calculating family poverty, these individuals are treated as single person families.
The Census Bureau does not use the term "working poor." The term "working poor" may mean different things to different data users, based on the question they are trying to answer, such as: