Thursday 23 March 2023

NSW Election Betting Says Most Likely Outcome Is Hung Parliament

Sportsbet and TAB are offering seat by seat betting on the NSW election this Saturday March 26. Interestingly, Ladbrokes have decided not to.

I derived implied probabilities from the seat by seat odds from Sportsbet and TAB and used them to simulate the election result. The method is discussed here

A simulation over 1,000,000 paths with a range of correlation parameters give a 70 - 75% probability of a hung parliament with a Labor minority government. The most likely outcome in the 93 seat NSW lower house is ALP 45, Coalition (LNP) 37, Greens 3 and 8 independents. 

With the support of 47 members required to govern, the Coalition has almost no chance. To form a minority government, they will likely need the support of all 8 independents, plus possibly the Greens, which will not happen. 

The Greens are highly likely to win Newtown, Balmain and Ballina, so let's assume they do. 

The almost certain independent wins are Lake Macquarie (left leaning Greg Piper), Sydney (left leaning Alex Greenwich) and Wagga Wagga (Joe McGirr - conservative but from a Labor family and not a big fan of the current government). Highly likely independent wins are Orange (Philip Donato), Barwon (Roy Butler) and Murray (Helen Dalton). All three are conservative; ex Shooters, Farmers and Fishers. 

Let's assume the above seats give us 6 independents, of which 3 will likely support the LNP. 

Kiama is an interesting seat. Holsworthy MP Melanie Gibbons is running as the LNP candidate, with sitting Liberal MP Gareth Ward running as an independent after being charged with sexual offences.

Then we have the challenges to normally LNP seats by the "Teals" in Manly, North Shore, Pittwater, Wakehurst and Wollondilly. It is possible that some of these 5 and possibly Kiama will elect independents. The simulation implies at least 1 or 2. 

The outcome is that if Labor get close to 47 seats, even significantly above 40, they can probably count on Greg Piper and Alex Greenwich, plus possibly Joe McGirr to form a governemnt without having to try to deal with the Greens, who will almost certainly try to hold them to ransom with delusional demands; self-righteous, glorified uni students that they are. 

The probability that the Coalition get to 43 seats and can rely on the 3 ex Shooters plus possibly Gareth Ward or Joe McGirr or one of the Teals is very low: about 8%. 

Thus, the overwhelmingly most likely outcome is a Labor government, probably a minority one, supported by the left leaning independents and possibly requiring a deal with the Greens, the latter option leading to chaos.


Post election:

Looks like the money was on the money. Betting odds aren't always a good predictor, but in this election they were: ALP 45 LNP 36 GRN 3 and 9 other independents. We were only one cross bencher out.

There were a few seats paying 1.10 to 1.20 which at one time looked like they might swing to Labor: Holsworthy, Ryde and Terrigal, but the Coalition just got over the line in all 3.