Post-election pendulum for the 1996 Australian federal election

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The Mackerras pendulum as a way of predicting the outcome of an election contested between two major parties in a Westminster style lower house legislature such as the Australian House of Representatives, which is composed of single-member electorates and which uses a preferential voting system such as a Condorcet method or instant-runoff voting.

The pendulum works by lining up all of the seats held in Parliament for the government, the opposition and the crossbenches according to the percentage point margin they are held by on a two party preferred basis. This is also known as the swing required for the seat to change hands. Given a uniform swing to the opposition or government parties, the number of seats that change hands can be predicted. [1]

Government seats (94) [2]
Marginal
Northern Territory NT Nick Dondas CLP0.37
Paterson NSW Bob Baldwin LIB0.43
Canning WA Ricky Johnston LIB0.69
Lilley Qld Elizabeth Grace LIB0.73
Bendigo Vic Bruce Reid LIB0.88
Bowman Qld Andrea West LIB0.89
Makin SA Trish Draper LIB1.08
La Trobe Vic Bob Charles LIB1.37
Griffith Qld Graeme McDougall LIB1.47
Lindsay NSW Jackie Kelly LIB1.58
Kingston SA Susan Jeanes LIB2.01
McMillan Vic Russell Broadbent LIB2.07
McEwen Vic Fran Bailey LIB2.18
Cowan WA Richard Evans LIB2.39
Lowe NSW Paul Zammit LIB2.47
Deakin Vic Phil Barresi LIB2.48
Chisholm Vic Michael Wooldridge LIB2.59
Dickson Qld Tony Smith LIB3.17
Dunkley Vic Bruce Billson LIB3.36
Adelaide SA Trish Worth LIB3.52
Robertson NSW Jim Lloyd LIB3.56
Capricornia Qld Paul Marek NAT3.62
Ballarat Vic Michael Ronaldson LIB3.67
Murray Vic Sharman Stone LIB3.70 v NAT
Swan WA Kim Wilkie LIB3.71
Parramatta NSW Ross Cameron LIB3.87
Leichhardt Qld Warren Entsch LIB4.18
Page NSW Ian Causley NAT4.31
Bass Tas Warwick Smith LIB4.57
Eden-Monaro NSW Gary Nairn LIB4.76
Hughes NSW Danna Vale LIB4.89
Moreton Qld Gary Hardgrave LIB5.09
Stirling WA Eoin Cameron LIB5.17
Aston Vic Peter Nugent LIB5.59
Braddon Tas Chris Miles LIB5.70
Fairly safe
Gilmore NSW Joanna Gash LIB6.24
Macquarie NSW Kerry Bartlett LIB6.36
Parkes NSW Michael Cobb NAT6.50
Herbert Qld Peter Lindsay LIB6.59
Casey Vic Bob Halverson LIB6.65
Richmond NSW Larry Anthony NAT6.75
Corangamite Vic Stewart McArthur LIB7.69
Petrie Qld Teresa Gambaro LIB7.70
Wentworth NSW Andrew Thomson LIB7.83
Hindmarsh SA Chris Gallus LIB8.06
Grey SA Barry Wakelin LIB8.54
Forde Qld Kay Elson LIB9.70
Dawson Qld De-Anne Kelly NAT9.92
Sturt SA Christopher Pyne LIB9.99
Safe
Flinders Vic Peter Reith LIB10.07
Bennelong NSW John Howard LIB10.13
Hinkler Qld Paul Neville NAT10.36
Macarthur NSW John Fahey LIB10.69
Higgins Vic Peter Costello LIB10.73
Goldstein Vic David Kemp LIB10.94
Menzies Vic Kevin Andrews LIB10.99
Cowper NSW Garry Nehl NAT11.56
Longman Qld Mal Brough LIB11.59
Boothby SA Andrew Southcott LIB11.60
Hume NSW Alby Schultz LIB11.77
Tangney WA Daryl Williams LIB12.13
Pearce WA Judi Moylan LIB12.18
Cook NSW Stephen Mutch LIB12.28
Wannon Vic David Hawker LIB12.31
Forrest WA Geoff Prosser LIB13.64
Kooyong Vic Petro Georgiou LIB13.81
Kennedy Qld Bob Katter NAT14.49
Mayo SA Alexander Downer LIB15.16
Warringah NSW Tony Abbott LIB15.32
Lyne NSW Mark Vaile NAT15.44
North Sydney NSW Joe Hockey LIB15.56
Mackellar NSW Bronwyn Bishop LIB16.53
Ryan Qld John Moore LIB16.87
McPherson Qld John Bradford LIB17.00
Indi Vic Lou Lieberman LIB17.79
Fadden Qld David Jull LIB17.84
Fairfax Qld Alex Somlyay LIB18.09
Berowra NSW Philip Ruddock LIB18.40
Gwydir NSW John Anderson NAT18.51
Wide Bay Qld Warren Truss NAT18.53
Gippsland Vic Peter McGauran NAT18.64
New England NSW Ian Sinclair NAT19.18
Wakefield SA Neil Andrew LIB19.96
Very safe
Moncrieff Qld Kathy Sullivan LIB20.25
Fisher Qld Peter Slipper LIB20.34
Barker SA Ian McLachlan LIB20.89
Riverina NSW Noel Hicks NAT21.01
Farrer NSW Tim Fischer NAT21.23
Groom Qld Bill Taylor LIB21.28
Mallee Vic John Forrest NAT23.50
Mitchell NSW Alan Cadman LIB24.32
Maranoa Qld Bruce Scott NAT25.73
Bradfield NSW Brendan Nelson LIB25.77
O'Connor WA Wilson Tuckey LIB25.93
Opposition seats (49) [2]
Marginal
Dobell NSW Michael Lee ALP0.08
Brand WA Kim Beazley ALP0.23
Brisbane Qld Arch Bevis ALP0.36
Bruce Vic Alan Griffin ALP0.76
Lyons Tas Dick Adams ALP1.31
Rankin Qld Craig Emerson ALP1.35
Bank NSW Daryl Melham ALP1.41
Namadgi ACT Annette Ellis ALP1.51
Isaacs Vic Greg Wilton ALP1.56
Jagajaga Vic Jenny Macklin ALP2.71
Greenway NSW Frank Mossfield ALP3.39
Fremantle WA Carmen Lawrence ALP4.25
Barton NSW Robert McClelland ALP4.34
Franklin Tas Harry Quick ALP4.68
Wills Vic Kelvin Thomson ALP5.77 v IND
Fairly safe
Melbourne Ports Vic Clyde Holding ALP6.05
Werriwa NSW Mark Latham ALP6.21
Perth WA Stephen Smith ALP6.46
Corio Vic Gavan O'Connor ALP6.80
Hunter NSW Joel Fitzgibbon ALP6.97
Chisholm Vic Neil O'Keefe ALP7.03
Port Adelaide SA Rod Sawford ALP7.05
Fraser ACT John Langmore ALP7.32
Canberra ACT Bob McMullan ALP7.52
Shortland NSW Peter Morris ALP8.15
Charlton NSW Kelly Hoare ALP9.32
Bonython SA Bob Brown ALP9.32
Safe
Kingsford Smith NSW Laurie Brereton ALP10.15
Hotham Vic Simon Crean ALP10.56
Newcastle NSW Allan Morris ALP11.19
Reid NSW Laurie Ferguson ALP11.38
Watson NSW Leo McLeay ALP11.68
Denison Tas Duncan Kerr ALP11.79
Holt Vic Gareth Evans ALP12.81
Cunningham NSW Stephen Martin ALP12.91
Blaxland NSW Paul Keating ALP12.98
Sydney NSW Peter Baldwin ALP13.80
Prospect NSW Janice Crosio ALP13.91
Chifley NSW Roger Price ALP14.54
Grayndler NSW Anthony Albanese ALP16.38
Calwell Vic Andrew Theophanous ALP17.19
Fowler NSW Ted Grace ALP18.27
Lalor Vic Julia Gillard ALP18.51
Maribyrnong Vic Bob Sercombe ALP18.85
Throsby NSW Colin Hollis ALP19.62
Very safe
Melbourne Vic Lindsay Tanner ALP20.21
Scullin Vic Harry Jenkins ALP20.74
Gellibrand Vic Ralph Willis ALP21.23
Batman Vic Martin Ferguson ALP21.31
Crossbench seats (5)
Oxley Qld Pauline Hanson IND [a] 4.66 v ALP
Curtin WA Allan Rocher IND7.28 v LIB
Calare NSW Peter Andren IND13.32 v NAT
Kalgoorlie WA Graeme Campbell IND10.35 v ALP
Moore WA Paul Filing IND15.48 v ALP
  1. Pauline Hanson had been disendorsed as the Liberal candidate and ran as an independent, but she remained a Liberal on the ballot paper

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The following is a pendulum based on the outcome of the 2010 federal election and changes since, including the redistributions of seats in South Australia and Victoria. It is a Mackerras pendulum, invented by psephologist Malcolm Mackerras, which works by lining up all of the seats held in Parliament according to the percentage point margin on a two-candidate-preferred basis. The two-party result is also known as the swing required for the seat to change hands. Given a uniform swing to the opposition or government parties in an election, the number of seats that change hands can be predicted. Swings are never uniform, but in practice variations of swing among the Australian states usually tend to cancel each other out. Seats are arranged in safeness categories according to the Australian Electoral Commission's (AEC) classification of safeness. "Safe" seats require a swing of over 10 per cent to change, "fairly safe" seats require a swing of between 6 and 10 per cent, while "marginal" seats require a swing of less than 6 per cent. The swings for South Australian and Victorian seats are notional, based on calculations by the AEC.

At the 2016 federal election of the 150 House of Representatives seats the Liberal/National Coalition won 76, a one-seat majority, Labor won 69 seats and crossbenchers won the remaining five. A redistribution in 2017/18 changed the representation entitlements. For the next election, the number of seats in the House will increase to 151, South Australia will lose a seat, Victoria and the Australian Capital Territory (ACT) will gain one seat each.

The Coalition won the 2013 federal election with 90 of 150 lower house seats on a current 17-seat, 3.65-point two-party swing, defeating the 6-year Labor government. Labor holds 55 seats while crossbenchers hold the remaining five. The Division of Fairfax was the last seat to be declared.

This is a Mackerras pendulum for the 2016 Australian federal election.

The Coalition won the 2016 federal election with a one-seat majority 76 of 150 lower house seats. Labor holds 69 seats while crossbenchers hold the remaining five.

The Labor party won the 2018 state election by winning 55 of the 88 lower house seats. The coalition won 27 seats while the Greens and independents won 3 each.

The Coalition won the 2019 federal election with a three-seat majority of 77 of 151 lower house seats. Labor holds 68 seats, and crossbenchers hold the remaining six.

The Mackerras pendulum was devised by the Australian psephologist Malcolm Mackerras as a way of predicting the outcome of an election contested between two major parties in a Westminster style lower house legislature such as the Australian House of Representatives, which is composed of single-member electorates and which uses a preferential voting system such as a Condorcet method or IRV.

The Australian Labor Party won the 2022 federal election, winning 77 of 151 seats in the House of Representatives. The Coalition holds 58 seats, and crossbenchers hold the remaining 16.

The Mackerras pendulum as a way of predicting the outcome of an election contested between two major parties in a Westminster style lower house legislature such as the Australian House of Representatives, which is composed of single-member electorates and which uses a preferential voting system such as a Condorcet method or instant-runoff voting.

The Mackerras pendulum as a way of predicting the outcome of an election contested between two major parties in a Westminster style lower house legislature such as the Australian House of Representatives, which is composed of single-member electorates and which uses a preferential voting system such as a Condorcet method or instant-runoff voting.

The Mackerras pendulum was devised by the Australian psephologist Malcolm Mackerras as a way of predicting the outcome of an election contested between two major parties in a Westminster style lower house legislature such as the Australian House of Representatives, which is composed of single-member electorates and which uses a preferential voting system such as a Condorcet method or IRV.

References

  1. Sakkal, Paul; Rooney, Kieran (14 November 2023). "Veteran Liberal Party MP Russell Broadbent quits party, moves to crossbench". The Sydney Morning Herald.
  2. 1 2 Newman, G; Kopras, A (4 November 1996). "Federal Elections 1996" (PDF). Background Paper 6 1996-97. Parliamentary Research Service. ISSN   1037-2938 . Retrieved 2024-01-09.