|
1999 Redistribution-NSW Proposals
Gerard Newman
Andrew Kopras
Statistics Group
10 August 1999
Introduction
On 16 July 1999 the Redistribution Committee for New South Wales announced
proposed changes to the boundaries of Commonwealth Electoral Divisions
in that State. The redistribution in NSW is one in a series of redistributions
that will take place in 1999; the others being South Australia (expected
to be finalised by the end of August) and Tasmania (proposals expected
to be announced by the end of August).
This Research Note outlines a methodology for analysing the effects of
electoral redistributions and uses that methodology to estimate the electoral
consequences of the proposed redistribution in NSW.
Methodology
The methodology used in this paper is based on the allocation of Census
Collection Districts (CCD) to the proposed Divisions. Collection Districts
are the smallest spatial unit used for the collection of Census data and
are also used by the Australian Electoral Commission for electoral redistribution
purposes.
As a consequence of the marking of the Electoral Roll at election time
the Australian Electoral Commission (AEC) is able to generate data showing,
for each of the 34 500 Census Collection Districts in Australia, the number
of electors in the CCD who voted at specific polling places. Thus for
any CCD in Australia the number of electors who voted at particular polling
places is known. However, this data is insufficient as it does not contain
information on how they voted. To obtain this it is necessary to assume
that those electors from the CCD who voted at a particular polling place
voted the same way as the polling place as a whole. Thus the two-party
preferred voting data for each polling place can be used to estimate the
two-party preferred votes for each CCD group of voters at the polling
place. This data can then be aggregated for each group in the CCD to arrive
at an estimated two-party preferred vote figure for each CCD.
The estimated two-party preferred votes for redistributed Electoral Divisions
can then be calculated by aggregating the two-party preferred votes for
each CCD in the proposed Division.
Highlights
The Redistribution Committee has proposed changes to all Electoral Divisions
in NSW, although in some cases the boundary changes have resulted in little
or no change to the two-party preferred votes for the Division. The table
on the reverse page shows the two-party preferred votes at the 1998 House
of Representatives election on the actual boundaries and estimated for
the proposed boundaries. Figures for Newcastle are not available.
The main changes are proposed for the Divisions of Macarthur, Parramatta,
Paterson and Lindsay.
Macarthur has been changed from a reasonably safe Coalition seat
with a margin of 5.6% to a marginal ALP seat (margin 1.7%) with the inclusion
of parts of Campbelltown from Werriwa and the transfer of large parts
of the Southern Highlands to Hume.
Parramatta has also changed from a Coalition seat (margin 1.1%)
to a marginal ALP seat (margin 2.4%) with the inclusion of Westmead, Marys
Hill and Harris Park from Reid and the loss of Northmead and North Rocks
to Mitchell.
The reverse has occurred in Paterson, which has been changed from
a marginal ALP seat (margin 1.2%) to a very marginal Coalition seat (margin
0.3%) with the loss of Maitland to Hunter and the acquisition of Forster-Tuncurry
from Lyne.
The Division of Lindsay has been made safer for the Coalition
(margin 2.1%) with the loss of St Clair to Prospect.
1999 Redistributionn-NSW Proposals

|