2025 House Of Reps Postcount Summary, Links Hub And Classic 2PP Seats Page

FINAL SEAT TOTAL ALP 94 L-NP 43 IND 10 GRN 1 CA 1 KAP 1

SEATS APPARENTLY CHANGING (defections disregarded) 

L-NP to LABOR: Banks, Bass, Bonner, Braddon, Deakin, Dickson, Hughes, Leichhardt, Moore, Sturt, Forde, Petrie, Menzies (see below)

GREENS to LABOR: Brisbane, Griffith, Melbourne

L-NP to IND: Calare, Bradfield

IND to L-NP: Goldstein

SEATS IN SIGNIFICANT DOUBT - seats shown in bold have now been discusssed in detail either here or on one of the linked pages:

None anymore

Seats I am not currently considering in doubt that were in the lists above

Flinders, Monash, Forrest, Grey, Fisher, Longman: Liberal/LNP retains 

Wills, Fremantle, Bendigo, Bullwinkel, Bean, Calwell: Labor retains

Goldstein: expected Liberal gain

Melbourne: ALP gain

Ryan: Green retain

Kooyong:  IND retain

Bradfield: IND gain

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Seat Betting As Bad As Anything Else At Predicting The 2019 Federal Election

Advance Summary

1. Seat betting markets, sometimes believed to be highly predictive, did not escape the general failure of poll and betting based predictions at the 2019 federal election.

2. Indeed, seat betting markets were significantly worse predictors of the result than the national polls through the election leadup, and only converged with polling-based models to reach a prediction that was as inaccurate as the national polls at the end.

3. Seat betting predicted fourteen seats incorrectly, but all of its errors in Labor vs Coalition contests, in common with most other predictive methods, were in the same direction.

4. Seat betting markets did vary from a national poll-based outlook in several seats, but their forecasts in such cases were about as often misses as hits.

5. This is the third federal election in a row at which seat betting has failed to show that it is a useful predictor of classic (Labor vs Coalition) seat-by-seat results in comparison with simpler methods.  

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With all House of Representatives seats now declared, it's time for a regular post-election feature on this site, a review of how seat-by-seat betting fared as a predictive method.  I have been interested in this subject over the years mainly to see whether seat betting contained any superior insight that might be useful in predicting elections.  In 2013 the answer was a resounding no, in 2016 it was a resounding meh, and surely if seat betting could show that it knew something that other sources of information didn't, 2019 would be the year! Even if seat betting wasn't a very good predictor, if it was not as bad as polling or headline betting this year, that would be something in its favour.

2019 saw the first failure in the headline betting markets since 1993, but it was a much bigger failure than that.  In 1993 Labor were at least given some sort of realistic chance by the bookies, and ended up somewhere in the $2-$3 range (I don't have the exact numbers).  This year the Coalition were $7.00 to Labor's $1.10 half an hour before polls closed - just an implied 14% chance -  and Sportsbet had already besmirched itself in more ways than one by paying out early (which I think should be banned when it comes to election betting, but that's another story).  The view that "the money never lies" has been remarkably immune to evidence over the years, but surely this will be the end of it for a while.

How Did The Super Saturday Seat Polls Go?

With final results for the Super Saturday by-elections now available, including preference flows, it is worthwhile reviewing the accuracy of the seat polling for these by-elections.  Recently I have posted a few times here about seat polling - see Is Seat Polling Utterly Useless? and Why Is Seat Polling So Inaccurate?  The preferencing results of the Longman by-election are also of special interest to the debate about Newspoll preferences, as the first test of Newspoll's changed methods at any federal election.

We can put that one to bed right away: the preference flow from One Nation to the Coalition in Longman was a massive 67.74%.  This should not be taken as a sign of quite how strongly One Nation preferences would flow nationally, since they did preference the LNP in this seat but would not necessarily do so in every seat, and since LNP preferences flowed strongly to One Nation in the area at the Queensland election even in the seat where the party preferenced Labor.  But it does show that it is entirely reasonable for pollsters to assume that 2016-election preferences can't be trusted in the case of One Nation.

Super Saturday By-Elections Live And Postcount

BRADDON: CALLED Keay (ALP) retain
LONGMAN: CALLED Lamb (ALP) retain
MAYO: CALLED Sharkie (CA) retain
FREMANTLE: CALLED Wilson (ALP) retain
PERTH: CALLED Gorman (ALP) is new MP, retaining seat
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Braddon Swings

Here is a graph showing the relationship between the vote for the independent Craig Garland and the 2PP swing in Braddon:

You can see maps of the Garland vote and the 2PP swing over at The Tally Room.  The Liberals did very well on 2PP swing on the West Coast, were smashed on King Island and the west end of the coast (Wynyard - Stanley area where fishing is important) and got small swings in Ulverstone and Devonport-Latrobe.

Longman By-Election

LONGMAN (ALP 0.8%)
Cause of by-election: Incumbent resignation (ineligible under Section 44)
Outlook: Your guess is probably as good as mine.

I've finally found the time to write a detailed post about the prospects for the Longman by-election.  This won't be anywhere near as long as my Braddon guide but I think it is worth explaining why we are seeing Labor struggling in the polls, the betting and in commentary perceptions in this seat. (That said quite a few people think Labor will win Longman but lose Braddon instead.)  When I first wrote about these by-elections, I thought national polling gave Labor enough advantage to probably just hold Longman, but since then Labor's national position has declined.  Labor may still win the seat, but their position is quite fragile.

Why Is Seat Polling So Inaccurate?

The accuracy of Australian seat polling has been an important topic lately, especially given the coming by-elections.  By-elections are very difficult to forecast.  Even after throwing whatever other data you like at them (national polling, government/opposition in power, personal vote effects, state party of government) they are less predictable than the same seats would be at a normal election.  So it would be nice if seat polling would tell us what is going to happen in them.

Unfortunately single-seat polling is very inaccurate.  I discussed this in a recent piece called Is Seat Polling Utterly Useless?, where I showed that at the 2016 federal election, seat polling was a worse predictor of 2PP outcomes than even a naive model based on national polling and assumed uniform swing.  The excellent article by Jackman and Mansillo showed that seat polling for primary votes was so bad that it was as if the polls had one sixth of their actual sample size.  It doesn't seem that seat polls are useless predictively, but we certainly can't weight them very highly.

The Expected "Super Saturday" By-Elections

Today's four resignations from the House of Representatives following the Section 44 disqualification of Labor Senator Katy Gallagher is expected to trigger a day of at least five by-elections, or at least a cluster of by-elections close to each other.  The following seats are affected:

Braddon, TAS (ALP, 2.2%)
Fremantle, WA (ALP, 7.5%)
Longman, QLD (ALP, 0.8%)
Mayo, SA (Centre Alliance vs Lib, 5.0%; Lib vs ALP 5.4%)
Perth, WA (ALP, 3.3%) 

See The Tally Room for detailed histories of these seats.  Also see the Poll Bludger thread for Perth.  All seats will be contested on the old boundaries, irrespective of redistributions.

It's possible that given the strictness of the High Court's ruling, other MPs may come under pressure to resign or be referred to the High Court (note: as of Friday the media are suddenly all over the Anne Aly story, which has been known via Jeremy Gans' Twitter comments for months), though the Coalition may not be in any great hurry to hunt down any more and invite more scrutiny of its own remaining unclear cases.  The by-elections are not just a nuisance for Labor, but also for the Coalition, which must either throw resources into contesting them seriously or else chicken out and leave voters wondering what all the fuss was about.

Australia has never had a day with five federal by-elections before, so it would be quite a novelty.  Three were held on the same day in 1981 and 1984.  In 1994 four were held across three weekends following a cluster of resignations, but the resignations came on different days.  At state level, NSW has often held multiple by-elections on the same day.