Post-election pendulum for the 2018 Victorian state election

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The Labor party won the 2018 state election by winning 55 of the 88 lower house seats. The coalition won 27 seats (Liberal 21 and Nationals 6) while the Greens and independents won 3 each.

Classification of seats as marginal, fairly safe or safe is applied by the independent Australian Electoral Commission using the following definition: "Where a winning party receives less than 56% of the vote, the seat is classified as 'marginal', 56–60% is classified as 'fairly safe' and more than 60% is considered 'safe'." [1]

Pendulum

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 pendulum works by lining up all of the seats held in Parliament for the government, the opposition and the cross benches 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.

Labor seats - 2018
SeatMemberPartyMargin
Marginal
Bayswater Jackson Taylor ALP0.39%
Hawthorn John Kennedy ALP0.42%
Nepean Chris Brayne ALP0.91%
Northcote Kat Theophanous ALP1.71% v GRN
Mount Waverley Matt Fregon ALP1.85%
Box Hill Paul Hamer ALP2.11%
Bass Jordan Crugnale ALP2.39%
Ringwood Dustin Halse ALP2.82%
Burwood Will Fowles ALP3.31%
Melton Steve McGhie ALP4.29%
South Barwon Darren Cheeseman ALP4.60%
Richmond Richard Wynne ALP5.46% v GRN
Fairly safe
Geelong Christine Couzens ALP6.23% v IND
Narre Warren South Gary Maas ALP6.90%
Pascoe Vale Lizzie Blandthorn ALP8.58% v IND
Monbulk James Merlino ALP8.60%
Werribee Tim Pallas ALP8.78% v IND
Eltham Vicki Ward ALP9.09%
Frankston Paul Edbrooke ALP9.74%
Narre Warren North Luke Donnellan ALP9.76%
Safe
Wendouree Juliana Addison ALP10.26%
Cranbourne Pauline Richards ALP10.98%
Bellarine Lisa Neville ALP11.45%
Bentleigh Nick Staikos ALP11.92%
Carrum Sonya Kilkenny ALP11.95%
Bendigo East Jacinta Allan ALP12.11%
Buninyong Michaela Settle ALP12.24%
Ivanhoe Anthony Carbines ALP12.36%
Niddrie Ben Carroll ALP12.59%
Mulgrave Daniel Andrews ALP12.71%
Mordialloc Tim Richardson ALP12.90%
Albert Park Martin Foley ALP13.13%
Macedon Mary-Anne Thomas ALP13.18%
Sunbury Josh Bull ALP14.33%
Altona Jill Hennessy ALP14.57%
Keysborough Martin Pakula ALP14.85%
Oakleigh Steve Dimopoulos ALP15.78%
Essendon Danny Pearson ALP15.86%
Yan Yean Danielle Green ALP17.03%
Bundoora Colin Brooks ALP17.42%
Clarinda Meng Heang Tak ALP17.43%
Sydenham Natalie Hutchins ALP17.86%
Tarneit Sarah Connolly ALP18.02%
Bendigo West Maree Edwards ALP18.55%
Lara John Eren ALP19.14%
Very safe
Yuroke Ros Spence ALP20.26%
Preston Robin Scott ALP20.70% v GRN
St Albans Natalie Suleyman ALP21.54%
Williamstown Melissa Horne ALP22.07%
Dandenong Gabrielle Williams ALP23.93%
Mill Park Lily D'Ambrosio ALP24.9%
Kororoit Marlene Kairouz ALP25.65%
Thomastown Bronwyn Halfpenny ALP27.19%
Footscray Katie Hall ALP28.11%
Broadmeadows Frank McGuire ALP30.28%
Coalition seats - 2018
SeatMemberPartyMargin
Marginal
Ripon Louise Staley LIB0.02%
Caulfield David Southwick LIB0.27%
Sandringham Brad Rowswell LIB0.64%
Gembrook Brad Battin LIB0.79%
Hastings Neale Burgess LIB1.07%
Brighton James Newbury LIB1.12%
Forest Hill Neil Angus LIB1.16%
Ferntree Gully Nick Wakeling LIB1.64%
Croydon David Hodgett LIB2.12%
South-West Coast Roma Britnell LIB2.31%
Eildon Cindy McLeish LIB2.44%
Benambra Bill Tilley LIB2.45% v IND
Evelyn Bridget Vallence LIB2.65%
Warrandyte Ryan Smith LIB3.88%
Kew Tim Smith LIB4.78%
Mornington David Morris LIB5.00%
Polwarth Richard Riordan LIB5.40%
Rowville Kim Wells LIB5.69%
Bulleen Matthew Guy LIB5.77%
Fairly safe
Malvern Michael O'Brien LIB6.1%
Narracan Gary Blackwood LIB7.26%
Safe
Ovens Valley Tim McCurdy NAT12.63%
Gippsland South Danny O'Brien NAT15.33%
Euroa Steph Ryan NAT15.44%
Gippsland East Tim Bull NAT17.59%
Very safe
Lowan Emma Kealy NAT23.48%
Murray Plains Peter Walsh NAT23.95%
Crossbench seats - 2018
Mildura Ali Cupper IND0.34% v NAT
Brunswick Tim Read GRN0.57% v ALP
Melbourne Ellen Sandell GRN1.32% v ALP
Morwell Russell Northe IND1.84% v ALP
Shepparton Suzanna Sheed IND5.3% v LIB
Prahran Sam Hibbins GRN7.54% v LIB

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References

  1. "State Election 2018 - Summary - Victorian Electoral Commission". www.vec.vic.gov.au. Retrieved 11 December 2018.