Polls and betting market update

The odds at Sportsbet have settled down following the reassessment that occurred immediately after the Trump election in the United States. At the moment, the betting market sees a 45 per cent probability of a Labor Government and a 55 per cent probability of a Coalition government. Note: the gaps in the next few charts represent the days where I did not collect odds data.

In aggregate, the opinion polls suggest the Coalition would secure a larger two-party preferred vote share compared with Labor (50.6 to 49.4 per cent). However, given the large number of independents and Greens likely to be elected to the House, it is difficult to predict which party would form (probably minority) government if the current two-party preferred (2pp) polls were replicated at the next election. 

The primary vote aggregations suggest that the Coalition and Others are strengthening over the past month while Labor and the Greens are down. The Greens appear to have lost around a percentage point over the past six months or so. 

And finally, a quick look at the attitudinal polling.

Update: betting market and opinion polls 25 November

In the days following the Trump win in the United States, the betting market for the Prime Minister's party after the next Australian Federal election was a little volatile. It appears to have settled with the Coalition as slight favourite (55% probability). This reverses the position of the two major parties immediately prior to the US election. 

Apologies for the gaps in the previous charts. For various reasons I was not able to capture the odds data every day. The continuous lines represent consecutive days on which I was able to collect odds.

The two-party preferred voting intention polls now have the Coalition ahead (on average). However, given the likely number of independents and minor parties in Parliament after the next election, it is a little difficult to be confident about the major party to form government. 

The estimated house-effects that arise from Gaussian Random Walk (GRW) Bayesian Aggregation above are as follows. Note: these two charts are reporting on the same underlying data. 

Turning to the primary voting intention, we can see some clear trends. The Coalition has improved its position while Labor has declined since the last election.

The ALP is below where it was at the last election. Labor would likely lose seats to the Coalition, the Greens and/or left-leaning independents, if the election reflected these poll results. 

The Coalition is ahead of its previous election performance, and should gain both Labor and perhaps independent seats at the next election. 

The Greens should either maintain their position or gain seats at the next election.

The independents will either maintain their seat count or lose seats at the next election (based on these poll results).

The attitudinal polling shows a remarkable shift in sentiment for a first-term government.

New polls: Newspoll and Resolve

Today's Australian had a new Newspoll (49-51 in the Coalition's favour), and the Fairfax media had a new Resolve Strategic Poll (50-50). All of my polling aggregation methods suggest that the Coalition is just ahead in the two-party-preferred voting intention metric. However, the only certainty is a hung Parliament. In this range, it is just too close to call. 

Note: in the charts above, the GRW model is a Gaussian Random Walk model where the vote-shares on any day and much the same as the vote shares on the day before. The GP model is a Gaussian Process model, where polls that are closer together in time are deemed to be more highly correlated. The GP model performs less well when the density of polling data is low (as with the first year of the series above), and at both ends of the series where it tends to revert to an underlying assumption about voting intention in the model (set to an average of the most recent 10 polls). I prefer the GRW model over the GP model. 

The primary votes are also moving around a little, with the major party votes up on recent trends, at the expense of the Greens and other minor parties.

The betting market sees the next election as pretty close to the proverbial toss-up, with the Coalition the favourite to form Government.  The gaps in the following charts are days in which I did not collect odds data from SportsBet.