ARIA vs RRMA

Using ARIA to Classify Remoteness: Comparability of the ARIA and RRMA indexes

This section provides an in-depth comparison of the ARIA and RRMA indexes of remoteness at the SLA and town levels. It includes analysis of the number of SLAs/towns, land area, total population and demographic characteristics of the populations living in the areas categorised by the indexes. In doing so, it should be stressed that the two indexes are not directly comparable; although they both measure remoteness, the inclusion of a population density measure and the categorisation structure of the RRMA index makes direct translation between the two indexes unviable. However, it is possible to divide cross-tabulate regions of Australia on the basis of their categorisation in the two indexes, and the tables and maps incorporated within this section illustrate this point.

In the following analysis, the 1996 update of the RRMA index was used. No changes were made to the 1991 methodology for the 1996 version of the classification but the remoteness values were updated based on 1996 census data. RRMA values were assigned to populated towns across Australia on the basis of the SLA in which they were located in 1996. The ARIA index employed in this analysis was the latest update of ARIA, generated in January 2000 for all populated towns and SLAs. SLAs classified by the ABS as 'Other Territories' or 'Off-Shore & Migratory' have been excluded from the data as they were not assigned remoteness values for both indexes. The analysis was conducted for 1,326 SLAs and 11,829 populated towns across Australia. A full listing of SLAs with their associated ARIA scores and RRMA categories is provided in the Appendix.

Number of SLAs and towns

Tables 6.1 and 6.2 show the categorisation of the ARIA and RRMA indexes on an SLA and populated town basis respectively, cross-tabulated by ARIA and RRMA category. It can be observed from the tables that there is, to a certain extent, a general degree of comparability between the two indexes. For example, no SLAs or towns classified by ARIA as 'Highly Accessible' fall in either of RRMA's remote zones. Additionally, only one SLA and 54 towns classified by ARIA as 'Accessible' are categorised as remote by RRMA - this is the SLA of French Island and its corresponding towns, which represents a special exception due to the different treatment of islands by the two indexes. Likewise, at the opposite end of the spectrum, no SLAs or towns classified by ARIA as 'Remote' or 'Very Remote' fall within RRMA's metropolitan zone. This result would in fact have been an impossibility due to the fact that most of the SLAs classified by RRMA as metropolitan (i.e. the SLAs in the Statistical Division of the capital cities and in the SSDs of other metropolitan centres) fall within or near to the urban centre boundary of centres classed as Category A or B service centres in the ARIA index.

Table 6.1: Cross-classification of SLAs by the ARIA and RRMA indexes

Table 6.2: Cross-classification of populated towns by the ARIA and RRMA indexes

The potential for comparability between the two indexes is highest in the zone categorised as remote by the two indexes - i.e. between the 'Remote' and 'Very Remote' ARIA categories and the 'Rem1' and Rem2' categories in RRMA. As shown in Table 6.1, of the 184 SLAs categorised as remote by either index, 131 (71.2%) were categorised as remote by both. Of those SLAs inconsistently classified between the indexes, the majority (46) were classified as remote by RRMA but 'Accessible' or 'Moderately Accessible' by ARIA. These SLAs were located primarily in a circular pattern outside Perth, in the Riverland area at the South Australian/Victorian border and in the SLAs near Brisbane's outer metropolitan area, as shown in Figure 6.1. The degree of concordance between the remote zones of the indexes as calculated on a town basis was 67.7%, with the discrepancy between this and the SLA concordance due to the greater freedom of towns to vary their ARIA values than SLAs.

Figure 6.1: Degree of concordance between ARIA and RRMA: SLAs defined as remote

Land Area and Density

As it is not possible for point localities to record an area or density, this section considers only SLAs. Table 6.3 cross-classifies land area measured in terms of kilometres squared by the ARIA and RRMA indexes. As shown in the table, the vast majority (80.7%) of Australia's land area falls within the zone categorised as remote by both indexes. Further, a significant additional area of land (420,849 km2) is located within the zone contested as remote by the indexes. Further, on the basis of the data shown in Table 6.3, the density of the concordant remote zone is 0.08 persons per kilometre square in comparison with a density in the contested zone of 0.33 persons. The relatively high population density recorded in the zone classified by ARIA as remote but not by RRMA would possibly explain the lower remoteness status of the relevant SLAs in the RRMA index.

Table 6.3: Cross-classification of SLAs by the ARIA and RRMA indexes: Land area (km2)

Table 6.4: Cross-classification of SLAs by the ARIA and RRMA indexes: Population density (persons per kilometre squared)

Source: ABS 1996 Census CDATA96 Time Series Dataset

Total Population

As shown in Table 6.5, the majority of the Australian population is concentrated in the RRMA M1/ARIA 'Highly Accessible' zone. However, a significant number of people (approximately 2.4 million) are resident in the zone designated 'Rural Other Area' by RRMA. Of these, approximately half are living in areas designated 'Highly Accessible' by ARIA. These factors have significant implications for the implementation of government policies and programs, as the 'Rural Other Area' zone has been targeted in the past as a basis for funding allocation and data dissemination. Many of the towns in this zone are in fact located at only short distances from the boundaries of the built up area, in which case their eligibility to receive a remoteness-related payment would appear to be in question. Table 6.6, which cross-classifies the population living in urban centres and localities of 200 people or more by the RRMA and ARIA indexes, shows a similar pattern. The table also reveals that approximately 300,000 people are living in urban centres and localities in the ARIA remote zones.

Table 6.5: Cross-classification of SLAs by the ARIA and RRMA indexes: Total Population 1996

Source: ABS 1996 Census CDATA96 Time Series Dataset

Table 6.6: Cross-classification of populated localities by the ARIA and RRMA indexes: Total population 1996, Centres containing 200+ population

Source: ABS 1996 Census CDATA96 Basic Community Profile Dataset

Produced by The National Key Centre for the Social Applications of GIS (GISCA), University of Adelaide 10 Feb 2000
Site last modified on 10 Feb 2000 by The National Key Centre for the Social Applications of GIS (GISCA), University of Adelaide