Appendix B - Family classification

A detailed overview of how families and households are enumerated by the census, and the data available for each, is given in an earlier report (Milligan et al. 2006). Further information can be found in Statistics New Zealand’s classifications and standards for dwellings, families and households (Statistics New Zealand, 1999a, 1999b, 1999c) and the census (Statistics New Zealand 2001). Importantly, families and households, as identified in the census, have specific definitions that may differ from their intuitive meanings. In particular, the range of family structures that can be identified is limited by the fact that the census is a dwelling-based survey;¹ that is, the highest level at which individuals are grouped is by common dwelling. As such, interpersonal relationships (familial or otherwise) among individuals living in the same dwelling are discernible, but those among individuals living in different dwellings are not.

The model for the census definition of family is the ‘nuclear’ unit, consisting solely of parents and children or partnered couples. These definitions are primarily based on social arrangements and ‘parents’ need not be the biological parents of their ‘children’, nor need couples be legally married. For example, two children who are parented by, and live only with, their grandmother in the same dwelling are classified as a family nucleus. Moreover, any group of children with a common parent or guardian (‘person in a parent role’) living in the same dwelling is considered part of the same family nucleus, provided they do not have any children of their own living in the same dwelling.² In contrast, individuals living without children or partners in the same dwelling are not classified as belonging to a family nucleus, and neither are groups of siblings living together or groups of unrelated people living together.

Census households consist of all those people usually living in the same dwelling, regardless of their inter-relationships.

B.1 Family type classifications

Statistics New Zealand categorises family nuclei into three broad groups based on the presence or absence of children and the number of parents. These groups are further classified according to the dependency status of any children present (Statistics New Zealand 1999a, 1999b, 1999c). A dependent child is any child in a family nucleus aged 15 years or younger, or aged 16 or 17 years but not in full-time employment. An adult child is defined as a child in a family nucleus aged 18 years or over, or aged 16 or 17 years and engaged in full-time employment (Statistics New Zealand 2001). The categories are shown in Appendix Table B.1.

In all censuses prior to 2001, family type was re-derived to ensure comparability.

Appendix Table B.1 Family type categories

B.2 Household composition classifications

Households have been categorised in each census based on the number and type(s) of family nuclei present, any other people present, and (in later censuses) the relationships between people outside family nuclei and those in them. The number of categories in this classification increased greatly from 1981 to 2001.

Although household composition is not used in the tables discussed in this report, it was found useful to investigate some relationships between families and households using this classification. To improve comparability, a concordance was used to amalgamate some categories in later years into a reduced scheme that could accommodate the earlier censuses. The comparable categories are shown in Appendix Table B.2. No variables were re-derived for household composition.

Note that where a household consists of a single family only, its composition category will coincide with the family’s type.

Appendix Table B.2 Comparable household composition categories

Footnotes

1. In the census, “a dwelling is any building or structure, or part thereof, that is used (or intended to be used) for the purpose of human habitation” (Statistics New Zealand 2001).
2. Same sex couples are not identifiable in census data prior to 1996.