Day 4 - 2025 Federal Election

Today I am looking at the individual seat betting markets. These markets are tricky to analyse because of the favourite-longshot bias problem. To reduce the impact of this problem, I multiply the odds from each seat by its square root. This has the effect of increasing the odds for longshot outcomes, and thus reducing their probability. To calculate probabilities I take the reciprocal of the odds and then adjust for the bookmaker's overround.

From the individual betting markets we can deduce which parties might win the election. For example, we can count the party that is ahead in each seat. This suggests that the punters think the most likely outcome is one in which no party secures 76 of the 150 seats to form government in their own right.

Day 3 - 2025 Federal Election

Around lunchtime every day I take a snapshot of the odds for the winner of the next Federal Election at sportsbet. I use it as a barometer of public intuition for who might win the next election. At the moment it is very close. Today the win probabilities are effectively 50/50 for both Labor and the Coalition (ignoring the long shot outcome of any other party). 

Day 2 - Federal Election 2025

Today I spent some time looking at the published two-party preferred (2pp) opinion poll estimates for each of the Australian states and territories. [Note: I have excluded Tasmania, the Northern Territory and the Australian Capital Territory because there was not enough polls for these jurisdictions]. 

We will start with the headline chart that shows the current state of polling compared with the outcome of the previous election. As you can see, with the exception of Queensland, Labor state polling is below what each State achieved at the 2022 Federal Election. In the three largest states, it is below 50 per cent. 

Friday 28 March - we have an Election date

It has happened. This morning a Federal election was called for Saturday 3 May. The Parliament has been prorogued (a fancy word for closed). The House of Representatives has been dissolved. The Government is now a caretaker government, and (by convention) it only takes major decisions in consultation with the Opposition.

Over the next six weeks I will be blogging most days on electoral and polling matters. Today we will look at the betting market and primary vote polling in the states.

The betting market

The betting market at sportsbet has moved around a bit over the past few days. Around noon today, it gave Labor a 52.6 per cent probability of winning the 2025 election. That is very close to even money, with Labor as the slight favourite going into this race.

Late March Update

An Australian Federal election is likely to called in the next few weeks, and could be called as early as this weekend. Yesterday, the betting market has saw Labor pull ahead as the favourite to form government after the election. 

Mid-March 2025 Update

Since Donald Trump was sworn in as the President of the United States of America, the Australian polls have been trending away from the Coalition. Now Labor is is ahead on all of my aggregation models of the two-party preferred vote. If an election was held now, the sizeable "third party" vote would see either Labor or the Coalition form minority government. 

There was movement at the station ...

With apologies to Banjo Patterson for the headline, we are seeing a significant change in the polls. Since the start of 2025 we have seen a significant drift in primary voting intention away from the mainstream parties (Labor and the Coalition) to the Greens and Others. One consequence of this drift has been a weakening in the Coalition's lead in the two-party preferred polls, especially if we allocate preference flows based on the flows at the previous 2022 election. We are also seeing Albanese firming in the attitudinal polls. 

Let's start with the first preference, primary vote polls. Both Labor and the Coalition have declined since the start of 2025.