Aggregated Polling

 Two Party Preferred

Primary votes

Aggregated polling

Aggregated Attitudinal Polling

I am now applying the same Bayesian aggregation techniques I use to the opinion polling. I wrote extensively about those techniques here. The results are as follows:

Albanese - preferred leader

Bayesian aggregation

Now that we have enough data (around 40 national polls since the last election), we can start looking at a Bayesian aggregation using a Gaussian random walk to estimate voting intention from day to day.  I will tease with the chart that intrigues me the most: the rise of the One Nation Party since the 2025 election.

Some movement on the betting market

Polling Update

It's time for another polling update. We will start with the primary voting intention polls. Of note, there is a substantial divergence between polling firms. In the last couple of weeks we can see one pollster with the Coalition primary vote share at 24 per cent and another at 33. On the other side of the fence one pollster had Labor's primary vote share at 33 per cent and another over 38 per cent. 

Overall, the Greens and Others are little changed since the election. Labor's post election honeymoon may be coming to an end. The Coalition's post-election decline may be stalling. One Nation's post-election renaissance may be slowing. However all of these observations are couched in the context of very noisy and somewhat contradictory voting intention data from the various polling firms.

Polling Update

The remarkable thing in the latest batch of polls is the continued rise of the One Nation Party.  

Polling update

Two party preferred

Summary outcome of the 2025 Australian Federal Election

Wow

Last night I was asked if I was surprised by the result. The short answer is yes! Not because Labor won (that was my working assumption) but that it won with such a thumping majority. The national two-party preferred vote is currently sitting at 55.37 per cent for Labor, with some 70 per cent of the vote counted. While I expect that total will come back a touch as the remaining vote is counted (postal votes often favour the Coalition), it will remain an historic win for Labor. Right now the ABC is projecting the following seat count in the new 150 seat Parliament:

• Labor - 85 seats (they won 77 seats in 2022, in a 151 seat Parliament)
• Coalition - 36 seats (previously 58)
• Greens - 0 seats (previously 4)
• Others - 10 seats (previously 12)
• Undecided - 19 seats

Polling fail?

Was it a polling fail? My initial thought is maybe. Again, its not that the polls got the winner wrong, but that they did not capture the scale of Labor's win. The average poll estimate since 1 April had Labor on 52.5 per cent of the two-party preferred vote (better than my Bayesian aggregation of 52.1 percent). The interim result is 2.9 percentage points off that mark. On the same metric, the 2019 polls missed by 2.9 percentage points. So far, only one poll since 1 April was better than the interim result for Labor. Nonetheless, because the postal and absentee votes can change things, we will need to wait until all the votes are counted before we come to the question of whether there was a polling fail. 

To be fair, I did warn over the past week that the under-dispersion in the polling data meant that the risk of a polling error was heightened. When I was asked on X/Twitter whether it is possible for the polls to “herd” in a way that underestimates support for the ALP, in contrast to 2019, when polls herded to overestimate it; I simply responded "yes".