Time for a short post ahead of tonight's South Australian state election, which I will be covering live on here from the close of polling and, as time permits, through the postcount over coming weeks.
This has been another state election to have seen remarkably little polling. The only statewide public polls have been two Newspolls by YouGov and one self-branded YouGov poll (the two versions employing different weightings). The first Newspoll had a 53-47 Labor 2PP lead, the final Newspoll had 54-46 (41 Labor 38 Liberal 9 Green 12 Other), and the YouGov in between had 56-44. There is very little sign of life for the Marshall government in all this, but it's still within the reach of polling error that it might lose the 2PP more narrowly (or if it's a big error, get around 50-50) and then, perhaps, get lucky enough with the distribution of votes to hang on in a hung parliament.
Using the 54-46 Newspoll as an input, my conditional probability model (see previous article) suggests that Labor would win the 2PP in around 26 seats to 20 for the Liberals (Mount Gambier is excluded from the model). However, there is a widespread expectation (including some remarkably short betting odds) that the ex-Liberal independents will all be re-elected despite the clouds hanging over all of them except Dan Cregan. That would end up with a 26-17-4 parliament. The seat model can't reliably predict which of the seats on 6-10% margins would fall, other than that on a 6% swing enough of them would be close enough to going that Labor should pick up a couple just by luck. A similar outlook is seen in betting odds, which continue to have Labor favourites in the low-hanging fruit of Adelaide, Newland, Elder and King, but not in any other Liberal seats.
Since my last article there was speculation about Steven Marshall perhaps losing Dunstan off a small union-commissioned Utting Research robopoll (insert numerous disclaimers accordingly) that had him behind 49-51. This made me look at the historic record of state Premiers who led their party to victory from Opposition at the previous election: do they get a personal vote boost for being Premier? I found that they do on average (about 1.5%) but with a lot of variation. So I've added a boost factor to my model.
The Newspoll has Marshall with a reasonable +1 net rating (47-46) but he trails Peter Malinauskas as Better Premier, 41-44. Another record would have to fall here for Marshall to win, since in the only previous case of a trailing Premier winning the election (SA 2010) the gap was two points. Malinauskas also has an outstanding net personal rating of +24 (54-30). This is the third highest I can find for a state Opposition Leader behind Isobel Redmond (SA 2010, +36) and Steve Bracks (Vic 1999, +28). It didn't do Redmond much good as she lost, but that loss was off a 2PP that an Opposition would now expect to win off.
A couple of seat modelling efforts well worth a look for this election are by Armarium Interreta and Australian Election Forecasting. The former has found that using data from the previous two elections (weighted 2:1 in favour of the last election) appears to work better than just using the last election's margins in each seat. The latter has noted that the 2PP in the Newspoll is based on respondent preferences (which are somewhat prone to favour Labor federally) and that a last-election estimate could be 53.2 to Labor (though the implosion of the SA Best vote makes any estimate difficult.) Both models highlight an issue with forecasting this election: because there have been so few polls, the 2PP might plausibly be 50 or 58 to Labor instead of 54, but it's more likely to be somewhere near the middle of that range.
Overall, none of the polling in the campaign has been much of a surprise, though the 44-56 YouGov was a bit of an eyebrow-raiser. Electoral history says the Marshall government's task is difficult (mainly because of federal drag) and no evidence in the campaign has shown otherwise.
Coverage tonight from 6:00 SA time, or earlier if I see anything worth reporting on.
I'm not quite sure why but Labor spent a brief time as favourite in Davenport too (with both Sportsbet and TAB) and is currently around $2. Much shorter than the other seats at similar margins.
ReplyDeleteMy guess is that Davenport looks like it's been hyped up quite a fair bit by Labor as a seat which might be trending its way due to its high level of wealth and education (similar to other seats in Melbourne).
DeleteI don't know if I agree, but at the end of the day betting markets are primarily driven by perception. If Labor's hyping up Davenport, and the Liberals apparently also consider it a prospective Labor gain, then the betting market odds will very likely shorten.
Labor has thrown a lot at Davenport judging by the amount of election material I have got through my letter box and they have a chance. Still I think Liberals being favourite is right.
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