New Zealand Socioeconomic Indices and Social Stratification
Measuring social strata—the hierarchical layers of society—is essential for researchers and policymakers to understand the distribution of resources, opportunities, and power. In New Zealand, several frameworks have been developed to quantify socioeconomic status (SES), moving from early indices based on education and income to complex algorithms analyzing human capital and geographic deprivation.
The Elley-Irving (E-I) Index
Published in 1972, Socioeconomic Status in New Zealand by Warwick B. Elley and Irving introduced a socioeconomic index that became one of the most cited works in the country's social sciences. Based on 1966 Census data, the Elley-Irving (E-I) index proposed six distinct social strata. These strata were determined by a combination of education and income, then grouped by occupation.
While researchers embraced the scale for its utility, it faced public backlash from critics who believed New Zealand was a classless society. Some media outlets even labeled it a "snobbery scale." Despite these misinterpretations, the E-I index remains a foundational tool for social research in New Zealand.
[ไม่มีภาพประกอบ]The New Zealand Socioeconomic Index (NZSEI)
In the 1990s, P. Davis et al. introduced the New Zealand Socioeconomic Index of Occupational Status, known as the NZSEI. Unlike earlier models, the NZSEI is based on a "returns to human capital" model of stratification. This approach views socioeconomic position as a result of the investments individuals make in their skills and education.
Originally utilizing 1991 Census data (n=1,051,926), the NZSEI generated scores for 97 occupational groups using an algorithm that factors in age, income, and education. To allow for direct comparison with the E-I and ISEI scales, these linear rankings are aggregated into six discrete Socio-economic Status (SES) groupings. The index was later updated using 2006 Census data.
While derived from data on employed individuals, the NZSEI can be applied to the broader population by referencing the previous occupation of retired or unemployed persons, or the occupation of the household's primary earner.
| SES | Population % | Mean Income ($000) | Income Diff. (M-F) % | Mean Education (Years) | Education Diff. (M-F) Years |
|---|---|---|---|---|---|
| 1 | 6.3 | 14.4 | 34% | 14.8 | -0.4 |
| 2 | 6.6 | 14.7 | 21% | 15.1 | -0.4 |
| 3 | 27.6 | 12.9 | 27% | 13.3 | -0.4 |
| 4 | 20.5 | 11.9 | -6% | 12.0 | -0.1 |
| 5 | 18.7 | 11.7 | 7% | 12.1 | -0.4 |
| 6 | 20.2 | 11.9 | 12% | 11.8 | 0.1 |
The data reveals a significant gender pay gap across most strata. In five of the six groups, males earn considerably more than females, with differences ranging from 7% to 34%. The only exception is SES group four, where female income is higher than male income.
Other Measures of Social Status and Deprivation
Beyond occupational indices, New Zealand utilizes other methods to measure social and economic standing:
- NZDep2006: An index of geographic deprivation based on nine variables: telephone access, benefit receipt, unemployment, household income, car access, single-parent families, lack of qualifications, home ownership, and overcrowding.
- School Deciles: A key measure within the education system used to target funding and support to schools based on the socioeconomic status of their students.
- Cultural Stratification: Authors Caldwell & Brown identified eight "hidden tribes" in New Zealand, categorizing social groups by location-based labels such as Remuera, North Shore, Grey Lynn, Balclutha, Otara, Raglan, Cuba Street, and Papatoetoe.
In 2013, Statistics New Zealand further refined these measurements by publishing the NZSEI06, which applied updated statistical techniques to 2006 Census data.
Key Facts
- The Elley-Irving (E-I) index (1972) was one of the first major tools to categorize NZ society into six social strata.
- The NZSEI uses a "returns to human capital" model, incorporating age, income, and education.
- Gender income disparities are prevalent in the NZSEI data, with males earning more in five out of six SES groups.
- The NZDep2006 measures deprivation geographically using nine specific socioeconomic variables.
- Deciles are the primary tool for allocating socioeconomic-based funding in New Zealand schools.
Frequently Asked Questions
What is the difference between E-I and NZSEI?
The Elley-Irving (E-I) index is an earlier model based on education, income, and occupation. The NZSEI is a more modern linear scale based on a "returns to human capital" model, using an algorithm to rank occupations before aggregating them into groups.
How is the NZSEI applied to unemployed or retired people?
The index can be extended to these populations by using their most recent previous occupation or by using the occupation of the main income earner in their household.
What variables are used in the NZDep2006 Index of Deprivation?
It uses nine variables: household income, unemployment, benefit receipt, home ownership, car access, telephone access, overcrowding, single-parent families, and lack of qualifications.
How does the New Zealand education system measure socioeconomic status?
The system uses "deciles," which are measures of socioeconomic status used specifically to target funding and support for schools.
What were the "hidden tribes" described by Caldwell & Brown?
These were eight social categories labeled after specific New Zealand towns or suburbs, including Remuera, Otara, and Cuba Street, to identify different social groups within the country.