Appendix B: Calibrating the Household Economic Survey
Like other microsimulation models, Taxwell relies on sample weights to adjust from sample to population values. Each individual, family and household in the dataset is assigned a weight which represents how common that unit's characteristics are across the population. This appendix provides details on how the HES data are reweighted for the purposes of this analysis.
The HES is provided by Statistics N.Z. with population weights attached to the unit record data and is designed to meet certain demographic benchmarks relating to the population distributions such as age and gender. As part of constructing the source dataset to determine tax liabilities, eligibility and entitlement to welfare payments (via Taxwell) and the attribution of in-kind benefits, this study requires calibrating the sample to additional benchmarks to reflect the population subgroups of interest. These include the number of benefit recipients and superannuitants in projected years in addition to the breakdown of the total population into demographic subgroups such age, gender and ethnicity.
A list of the 9 broad benchmark categories used for this study is provided in Appendix Table 1. These 9 broad categories consist of 129 benchmarks. There are 34 benchmarks for age and sex, 24 for the number of occupants by household, 6 regional, 2 Maori, 12 person type, 2 household type, 18 tenure, 7 benefit and 24 labour force benchmarks. The GREGWT SAS macro, produced by the Australian Bureau of Statistics (2000), was used to carry out calibration of the benchmarks listed above.[22]
| Category | Detailed description |
|---|---|
| Age/Sex | Number of people in each five year age bands from 0 to 79 and 80+ by gender. |
| Number of occupants | Number of households by region with 1,2,3 or 4+ occupants. |
| Region | Number of people in each region as provided by HES. |
| Maori | Number of people who self identify with the Maori ethnicity between 15 and 29 and > 30. |
| Person Type | Number of people living in specific family situations that determine receipt of Working for Families. |
| Household Type | Number of households that have 2 adults or other composition. |
| Tenure | Number of households that are owned, held by a trust or other by region. |
| Benefit | Number of people receiving core benefits during the year. |
| Labour Force | Number of people participating in the labour force by gender and 5 year age band from 15 to 69, and 70+.[23] |
