Sunday, October 21, 2018

The betting market on the morning after Wentworth

Some movement on the betting market overnight ...

House Coalition Odds ($) Labor Odds ($) Coalition Win Probability (%)
2018-10-20 BetEasy 3.20 1.30 28.89
2018-10-21 BetEasy 4.00 1.20 23.08
2018-10-20 Ladbrokes 3.25 1.28 28.26
2018-10-21 Ladbrokes 3.50 1.25 26.32
2018-10-20 Sportsbet 3.20 1.30 28.89
2018-10-21 Sportsbet 3.50 1.25 26.32
2018-10-20 William Hill 3.40 1.30 27.66
2018-10-21 William Hill 3.40 1.30 27.66

Monday, October 15, 2018

Polling update

Today we had an Ipsos poll (45-55 in Labor's favour) and a Newspoll (47-53) with vastly different interpretations. For Newspoll the story was one of steady Coalition improvement (47 is better than Morrison's debut at 44). For Ipsos it was one of no benefit from the recent leadership change. The last Turnbull poll under Ipsos was also 45-55.

In the Bayesian model, I have allowed for a discontinuity in public opinion on 23 August, and for a period of higher than normal volatility in day-to-day voting sentiment from 24 August to 1 October. The results are as follows.

Enough time has passed since the Coalition leadership change for the moving average models to start to come back into alignment with the Bayesian model. Not withstanding the Coalition bounce following the immediate polling collapse in reaction to the leadership change in August 2018, Coalition voting sentiment is as low now as it was at Turnbull's worst period in the polls in late 2017.

My primary vote model has decided to stop working. Actually, I upgraded to the latest versions of Stan and pystan, and I need to tweak the model to get it working again.