This publication describes the Non-ABS Structures of the Australian Statistical Geography Standard (ASGS). It is volume 3 of a series detailing the new ASGS. The first ASGS publication, Australian Statistical Geography Standard (ASGS): Volume 1 - Main Structure and Greater Capital City Statistical Areas, July 2011 (cat. no. 1270.0.55.001), was released in December 2010.
Purpose of the Non-ABS Structures of the ASGS
The Non-ABS Structures bring together those regions which are not defined by the ABS, but which are important to users of ABS statistics. ABS is committed to providing a range of statistics for these areas. They generally represent administrative regions and are approximated by Mesh Blocks (MBs), Statistical Areas Level 1 (SA1) or Statistical Areas Level 2 (SA2).
As the Non-ABS Structures represent regions that are subject to ongoing change, the ABS will release a revised publication for ASGS Non-ABS Structures in July each year. The individual structures will only be updated where significant change has occurred in the past year.
The Non-ABS Structures of the ASGS comprise eight hierarchies of regions. These are:
- Local Government Area (LGAs)
- Postal Areas (POAs)
- State Suburbs (SSCs)
- Commonwealth Electoral Divisions (CEDs)
- State Electoral Divisions (SEDs)
- Natural Resource Management Regions (NRMRs)
- Australian Drainage Divisions (ADDs)
- Tourism Regions (TRs)
Diagram 1 depicts the various ASGS Non-ABS structures, their component regions and how they interrelate.
DIAGRAM 1: ASGS NON-ABS STRUCTURES.
Each of the Non-ABS Structures have been approximated using one of three methods:
- LGAs have been constructed from MBs based wholly on location. The relatively small size of MBs and common boundary elements between LGAs and MBs, allowed them to match LGAs very closely.
- POAs, SSCs, CEDs, SEDs, NRMRs and ADDs have been constructed from SA1s. The size and boundary locations of the Non-ABS Structures are designed to meet a specific purpose for the source agency. SA1s are created to contain a broadly similar population, where possible, and therefore vary greatly in size. This means that boundary mismatches between the original and SA1-derived features are inevitable. In many instances the geographic match between the boundaries of SA1 derived Non-ABS Structure regions and SA1s was poor. This led to a level of ambiguity about which feature the SA1 should represent. To assist in overcoming this, the estimated dwelling count of MBs (the building blocks of SA1s) was used.
- TRs have been constructed using SA2s. TRs have historically been based on SLAs which have effectively been replaced by SA2s in the ASGS. TRs were developed using simple allocation of SA2s to TRs.
The SA1 derived Non-ABS Structures were compared with the SA1s in an attempt to match by location. They were also assigned estimated dwelling counts based on the MBs they contained. Four basic situations occurred:
1. There was a very close match between the Non-ABS Structure region and a single SA1. In this case the Non-ABS region, for example a gazetted locality, is represented by a single SA1 in the derived State Suburb layer.
2. The Non-ABS Structure region contains a number of SA1s. In this case the Non-ABS region, for example a Commonwealth Electorate, is represented by an aggregation of SA1s in the derived Commonwealth Electoral Division layer.
3. Several Non-ABS Structure regions fall within a single SA1. In this case not all Non-ABS regions, for example a postcode, can be represented in the derived Postal Areas layer. The SA1 can only be allocated to one postcode so estimated dwelling counts were used to determine which postcode contributed the most "population" to the SA1. The SA1 was allocated to this postcode.
4. Several Non-ABS Structure regions overlap several SA1s. In this case the Non-ABS regions, for example State Electoral Divisions, are represented by the SA1s that best represent them in the derived State Electoral Divisions layer. This allocation was made by comparing the MB-based estimated dwelling counts for each of the electorates and SA1s with those of the common MBs with the aim being to maximise the overlap. This resulted in Electoral Divisions being represented by the SA1 which they share the most "population" with. There may also be Non-ABS geography regions that are unable to be represented.
In future, as ABS Census Output systems are redeveloped, it may be plausible to construct more of the Non-ABS Structures from MBs to create more accurate approximations of areas such as postcodes and gazetted localities.
Supporting Material for this volume
The following supporting material is available from the ABS website as free downloads from http://www.abs.gov.au/geography
- Digital boundaries for all regions described in this publication as MapInfo Interchange Format files and ESRI shape files. The digital boundaries do not include spatial objects for unclassified or unincorporated records.
- Codes, labels and hierarchies for all regions described in this publication are available in '.csv' format.
The ABS will also develop a suite of correspondences for the Non-ABS Structures. These will be developed progressively from the first release of data from the 2011 Census of Population and Housing in June 2012. There are a large number of potential correspondences that could be generated, so only the most widely used and reliable will be available on the ABS website. Less widely used or problematical correspondences may be available by emailing firstname.lastname@example.org
The new series of ABS population weighted correspondences will be based on Mesh Blocks. This will mean they will be simpler and more accurate than the correspondences derived from earlier Census data. Correspondences, their derivation and use will be the subject of an Information paper to be released in December 2011.
For more details about the ASGS and future releases please refer to Australian Statistical Geography Standard (ASGS): Volume 1 - Main Structure and Greater Capital City Statistical Areas
, July 2011 (cat. no. 1270.0.55.001).
Relationship of the Non-ABS Structures with the 2006 Census Geographic Areas
The Non-ABS Structures include a number of structures previously published as Census Geographic Areas in 2006:
- Postal Areas
- State Suburbs
- Commonwealth Electoral Divisions
- State Electoral Divisions.
It also includes several new structures, previously excluded from the Census Geographic Areas:
- Local Government Areas - previously part of the Australian Standard Geographical Classification (ASGC)
- Tourism Regions
- National Resource Management Regions
- Australian Drainage Basins.
The Australian Indigenous Geographical Classification, which is now an ABS Structure of the ASGS and will be published separately in September 2011.
For more information on the previous Census Geographic Areas view the following publication, Statistical Geography: Volume 2 - Census Geographic Areas, Australia, 2006
(cat. no. 2905.0).
The Non-ABS Structures and their component spatial units are shown in Table 1.
TABLE 1, Summary of ASGS Non-ABS Structures
|Non- ASGS Structure |
|Component Spatial Unit |
|Local Government Area (LGAs) |
|MB, LGA, S/T |
|Postal Areas (POAs) |
|SA1, POA, S/T |
|State Suburbs (SSCs) |
|SA1, SSC, S/T |
|Commonwealth Electoral Divisions (CEDs) |
|SA1, CED, S/T |
|State Electoral Divisions (SEDs) |
|SA1, SED, S/T |
|Natural Resource Management Regions (NRMRs) |
|SA1, NRMR, S/T |
|Australian Drainage Divisions (ADDs) |
|SA1, ADD, S/T |
|Tourism Regions (TRs) |
|SA2, TR, S/T |
The number of records in the Non-ABS ASGS Structures is shown in Table 2.
TABLE 2, Counts for Non-ABS Structures (effective 1 July 2011)
|Spatial Unit ||Name |
|LGA(b) ||Local Government Areas |
|POA(c)(d) ||Postal Area |
|SSC(d) ||State Suburb |
|CED(c)(e) ||Commonwealth Electoral Division |
|SED(e) ||State Electoral Division |
|ADD(c)(d) ||Australian Drainage Division |
|NRMR(e) ||Natural Resource Management Regions |
|TR ||Tourism Regions |
|- nil or rounded to zero (including null cells) |
|(a) Other Territories (OT) includes the territories of Cocos (Keeling) Islands, Christmas Island and Jervis Bay. |
|(b) Includes LGA 9399 Unincorporated and LGA 9499 No usual address for each State/Territory. |
|(c) CEDs, POAs, and ADDs may cross State/Territory borders and can be counted more than once in individual State/Territory figures but only once in the Australia total. |
|(d) Includes records for Migratory - Offshore - Shipping, No usual address and Unclassified for each State/Territory. |
|(e) Includes records for Migratory - Offshore - Shipping and No usual address for each State/Territory. |