AUS Lat/Long Household Level DataPlus
The AUS Lat/Long Household Level
DataPlus set (GHSE) is a co-ordinate DataPlus set that
will return the latitude and longitude of individual
addresses in Australia.
Data Format
The data is referenced to the Delivery Point
Identifier (DPID).
Data
The data has been created from a variety of
sources reflecting the need to develop a solution that
is optimised for coverage and accuracy. Three geocoding
tools have been used to append latitude and longitude
to individual property addresses.
The geocoding tools use a method
of interpolation between known points. Such known points
are street intersections, significant road deviations,
and end-points of a house number sequence. Address numbers
between known points are allocated at equally spaced
intervals, and from this the ‘best estimate’
latitude and longitude for the property is derived.
An additional source is used to
compensate for otherwise poor coverage in some remote
rural areas and to extend the coverage of business addresses.
This source uses a spatial analysis technique, derived
from analysis of satellite and aerial photography.
Coverage
Business and residential addresses are included
Australia-wide. Coverage is more than 90% in major metropolitan
areas, around 80% in provincial and well-settled country
areas (better in cities and towns) and around 70% in
the more remote country areas.
Inevitably there is a time-lag
between construction of new buildings and the inclusion
of new addresses in the base data used for geocoding.
This time-lag may be up to two years but in total it
only affects a small proportion of the total address
file.
Accuracy
Accuracy is very high in major metropolitan and other
well-populated areas where conventional premises numbering
is widespread. However, an estimated tolerance of 50
metres should be expected due to the use of interpolation
in the methodology. In most cases the discrepancy will
be less than 50 metres.
Maintenance
The DPID data is currently refreshed by Australia Post
every quarter. Pacific Micromarketing re-codes the file
in line with this cycle.
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