An Examination of the Links between Parental Educational Qualifications, Family Structure and Family Wellbeing, 1981–2006

Appendix A - Working with census data

A.1 Confidentiality

Access to the data used in this study was provided by Statistics New Zealand in a secure environment, the Data Laboratory, designed to give effect to the confidentiality provisions of the Statistics Act 1975. Personal identification information supplied on the original census forms, such as name and address, is not carried over to the computer records held by Statistics New Zealand, and these details are therefore not available to Data Laboratory users. Further omissions eliminate the linking of individual-level records in the Data Laboratory data sets back to respondents.

In addition, all Data Laboratory output is subject to confidentiality rules set by Statistics New Zealand to further protect respondent confidentiality. The current rules are given in (Statistics New Zealand 2006). In particular, all frequencies in this report are randomly rounded to one of the nearest multiples of 3 (e.g., a count of 5 could become 3 or 6) to further guard confidentiality (Statistics New Zealand 2001). All percentages are calculated based on rounded counts. Derived statistics such as medians are not rounded. Given that the numbers presented are typically very large, rounding is expected to have no effect on the conclusions drawn.