Underlying concepts

The name of the variable is 'Household composition'.

The primary factor determining 'Household composition' is whether a family is present or not and whether or not other unrelated household members are present. For statistical purposes, family is defined as two or more people, one of whom is at least 15 years of age, who are related by blood, marriage (registered or de facto), adoption, step or fostering, and who are usually resident in the same household. The basis of a family is formed by identifying the presence of a couple relationship, lone parent-child relationship or other blood relationship. Some households will therefore contain more than one family.

'Household composition' replaced the ABS Standard Variable 'Household type' in 2005. The title 'Household type' has been used to describe this variable in the Census of Population and Housing since 1986, the 1992 Survey of Families in Australia and the Monthly Population Survey (MPS). The title 'Family Composition of Household' has been used in the Household Expenditure Survey (HES). Prior to the introduction of the 'Household type' standard in 1992, the MPS used a non-standard list of family and household types labelled as 'Household Type'.

The concept of 'Household' is nominally defined as: 

• One or more persons usually resident in the same private dwelling.

The System of National Accounts (SNA) definition is: 'a small group of persons who share the same living accommodation, who pool some, or all, of their income and wealth and who consume certain types of goods and services collectively, mainly housing and food.' The ABS definition varies from that of the SNA only in specifically allowing lone person households, and in removing any reference to consumption.

The variable 'Household composition' is defined as:

• The differentiation of households on the basis of the number of families present, and whether or not unrelated household members are present (if it is a family household), or the number of household members (if it is a non-family household).

The variable 'Household composition' is an attribute of the statistical unit 'household'. Indirectly it is also an attribute of the 'person' for all persons who are members of households.

The 'Household' is operationally defined as:

• One or more persons, at least one of whom is at least 15 years of age, usually resident in the same private dwelling.

The ABS does not seek to differentiate multi-household dwellings from single-household dwellings; the number of households in a private dwelling is always regarded as one.

Having established the relationship of all usual residents of the household to one another, and identified all families and other unrelated household members (if any) within the household, the operationalisation of 'Household composition' is summarised as follows:

• Households are allocated to categories of the 'Household composition' classification on the basis of the number of families identified in the household, whether unrelated household members are present in a family household and whether the number of household members is greater than one in a non-family household.

The identification of usual residents is essential to determine 'Household composition' because the 'Relationship in household' data on which family and household coding rely only applies to usual residents.

For those cases where visitors are within scope of the collection, households consisting of visitors only are coded to Supplementary category '02 Visitor only household'.

Household member relationships and family identification are carried out using the 'Relationship in household' and 'Family composition' classifications. For further details see the standards for those variables

The variable 'Household composition' applies to all households in private dwellings

The variable 'Household composition' aims to analyse the counting unit 'household', just as the variable 'Family composition' is used in analysing the counting unit 'family' and the variable 'Income unit composition' is used to group persons within households who pool income in social and labour statistical collections. The income unit, the family and the household describe concepts which are very closely related in practice. Even though they are fundamentally different ideas, when applied to a particular dwelling they will all often refer to the same set of people. This is because the family is defined as a subset of the household and many Australian households comprise only a single family and a single income unit.

The 'Household composition' classification does not distinguish between multifamily households where the families are related to each other (e.g. where siblings each with dependent children share a dwelling), and multifamily households where the families are not related to each other. If this distinction is required, it should be derived as the separate variable 'Relationship between families' using 'Relationship in household' data. See the 'Relationship between families' standard for more information. The 'Household composition' classification does not distinguish between income units.

The 'Household composition' concept is confined to private dwellings. In some surveys, a multi-stage area sample of dwellings separately identifies two categories of dwellings: private dwellings (houses, flats, etc.) and non-private dwellings (or 'Special dwellings') which include units such as hotels and motels. Persons living in non-private dwellings such as hospitals, prisons, homes for the aged, etc. are outside the scope of the classification.

Hotels, motels and serviced apartments may be thought to contain potential households, but the ABS excludes people in non-private dwellings from family coding due to operational constraints imposed by the nature of collection methodologies. Similarly in the case of the Census, household data are not collected from persons residing in non-private dwellings, either temporarily or for longer periods of time. Instead, each individual is administered a personal questionnaire. Consequently the Census does not identify households in non-private dwellings either. It should be noted that over time the types of dwellings categorised as private dwellings have expanded to include some retirement villages, caravans etc, effectively broadening the scope of dwellings considered private dwellings.