Why Hunter 2025 Can't Be Used To Do Last-Election Labor vs One Nation Preference Flows

With the very rapid rise of One Nation in recent national primary voting intention polling we are starting to see some pollsters offer a national alternative Labor-vs-One-Nation two-party figure.  DemosAU did this in its national Jan 5-6 poll where it found One Nation tied with Labor 50-50 while Labor led the Coalition 52-48, this off primaries of Labor 29 Coalition 23 One Nation 23 (more on that later) Greens 12 others 13.  A newish outfit curiously polling on the same dates, Fox&Hedgehog (founded post the 2025 election by a former Peter Dutton staffer) reported 56-44 to Labor vs One Nation off fairly similar primaries of Labor 29 Coalition 25 One Nation 21 Greens 14 others 11, compared to 53-47 for Labor vs Coalition.  So DemosAU has One Nation two points more competitive than Labor on a head to head with Coalition basis while Fox&Hedgehog has them three points worse.  (I'll add that by my last election preferences 48% 2PP for Coalition is pretty generous on the published DemosAU breakdowns, I get 47.4 as the average for their primaries.)

DemosAU attempted to use last-election preferences by using the flow in the seat of Hunter 2025 (the only federal case ever of a Labor vs One Nation finish) to model Coalition to One Nation flows, by assuming the Greens to One Nation vs Labor flow would be the same as the Greens to Coalition vs Labor flow, and also by assigning flows from Others 50-50 between Labor vs One Nation "As the composition of Others is not known".  (That last bit did strike me as a little curious unless they were also doing the same thing for Labor vs Coalition, given that the 2PP flow from others in 2025 was about 54.7% to Labor).  Fox&Hedgehog simply used respondent preferences.  

2025-2028 2PP Aggregate Methods Page

Because I have way too many things to do right now I decided in my usual fashion to do one more that isn't any of them!  Introducing my 2025-2028 federal 2PP polling aggregate, which at this very early stage sits at 56.3 to Labor, with an overall pattern of basically no 2PP movement since it had enough data to wake up on 29 June.  The above is a 7-day smoothed aggregate though it has been as high as 57.2 on individual daily readings, and as low (a 0.8 point outlier lasting one day only!) as 55.5.  By the end of the term who knows if 2PP will even still exist the way the Australian right are going after this year's drubbing, but for the meantime, here we are.  Differences will be detected with aggregates that use pollster-released 2PPs (these tend to have Labor losing support more quickly) and also my estimate is currently running about a point below Bludger Track but with a similarly flat trajectory.  

The aim of the aggregate is to present a frequently updated figure for what the current polls should be taken as saying collectively about the state of the two-party preferred contest.  This is never a prediction or a statement that the polls are right, it is just putting a number on where they're at. 

This aggregate works quite differently from previous aggregates that had a simple 5-3-2-1 week of release formula, and does so mainly because of the increasing frequency of polls with long in field periods or late releases.  The mathematics are kept simple enough that I should be able to understand if something is going wrong (edit: indeed I fixed one glitch overnight after two August polls were found to have been entered as July; it made very little difference), but are no longer readily hand calculable to make my treatment of data less chunky and arbitrary.  The working of this year's aggregate is below:

Poll Roundup: What Is Going On With Newspoll Preferences?

2PP Aggregate (Last-election preferences): 52.4 to Labor (-0.4 since last week,  -1.2 points in five weeks)
With One Nation adjustment, 51.8 to Labor 
Closest position since May last year
Labor would very probably win election held "right now", but would probably have a small to moderate majority

[Updated on 26 April at bottom of post]

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Normally I issue Poll Roundups every second Newspoll. Since the last one there's been the slight distraction of the Coalition's 30th consecutive 2PP Newspoll loss. This week's Newspoll was number 31 in a row, just two shy of equalling the longest losing streak held by Labor under Julia Gillard, but it was more significant for the discussion it has sparked about (i) Newspoll's preferencing methods (ii) the prospect of a Coalition recovery.  So firstly, a detailed discussion of the preferencing issue, and then a slightly shorter discussion of where things now stand in federal polling.

Newspoll as a brand name linked to a standard set of questions has a 33-year history in Australia.  However, in 2015 the company previously doing Newspoll for the Australian was wound up.  The Australian retained control over the brand, but its operation was contracted out to Galaxy Research (which in turn was recently acquired by YouGov).  While the questions didn't change when Galaxy took over, the methods did, with a mixture of robopolling and online polling replacing the old Newspoll's landline-only live phone polling, and an increase in average sample size.

2016 House Of Reps Figures Finalised

I'm not sure exactly when this happened, but sometime in the last two weeks while I have been away overseas, the AEC has released the final detailed set of federal election results.  Although all House of Representatives seat results were already known, the release of final information on two-party preference flows and preference distributions is very useful for many things, including assessing the performance of polls.  Final results are here.  This article is a general roundup of various details, and soon I will be using the figures to conduct an in-depth review of polling accuracy at the election, and after that to start a new polling aggregate model.  There is quite a backlog of other articles that I want to write, so I hope I can get through as many of these as possible in the next three weeks before another round of fieldwork.

The final two-party preferred result is 50.36% to the Coalition to 49.64% to the ALP.  This represented a clear success for the last-election method of preference prediction, which would have predicted a 2PP of 50.53% for the Coalition based on the primaries actually cast.  The respondent-preferences method (on average across polls using it) expected a shift in preferencing large enough to shift the 2PP result by at least 0.6 points (ie Labor would have won the 2PP).  This continues the superior track record of last-election preferences, and I will continue to treat respondent preferences with caution. 

Wonk Central: The Track Record Of Last-Election Preferences

NOTE: Updates for elections from 2016 on appear at the bottom of this article

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Advance Summary

1. This article uses historic data to examine how good preference flows from the previous election are at predicting preference flows at any given federal election.

2. Last-election preferences have been an industry standard following various failures by and problems with the respondent-preference method, especially its total failure at the 2004 election.

3. Using a model of minor-party breakdowns similar to that used by most pollsters, this article looks at expected versus actual preference flows at all federal elections since 1955.

4. The quality of data available on preference flows is better for elections from 1983 onwards.

5.  Since 1983, last-election preferences have predicted preference flows remarkably well at most elections.

6. However, last-election preferences substantially understated the flow to Labor at two elections in this time: 1990 and 2013.

7. The historical record of last-election federal preferences is so strong that claims that last-election preferences in polling are wrong should generally be treated with great caution (including now).