Tuesday, March 12, 2013

Newspoll 52-48

The latest Newspoll has a three point bounce in the Government's favour.

I am always amused at how the papers interpret poll-to-poll bounces. Most of the time, most of the movement in a poll-to-poll bounce is random noise. It is without meaning. Most likely, today is no different.

All of the polls agree that the Government is recovering from its February nadir, just not at the rate of three percentage points in a fortnight. The latest Bayesian aggregation follows.

Note of caution: the Bayesian aggregation is very good at picking turning points in the trend. It is less accurate at picking the actual vote share the parties enjoy at a particular point in time. The aggregation model assumes the population trend is the average of the bias across the (now 7) polling houses. My suspicion is that this average is currently biased.


Morgan has released another multi-mode poll. This one was not as favourable for the Government as today's Newspoll. In terms of the how respondents said they would preference, the result was a cataclysmic 57.5 to 42.5 in the Coalition's favour. Using preference flows from the last election, the result was only stonkingly bad for the government: 55.5 to 44.5 in the Coalition's favour. It is this latter figure I use in my Bayesian aggregation.

It is clearly too early to have a view on the stability and inherent house biases of this new polling technology from Morgan. Nonetheless, the Bayesian aggregation has shifted somewhat with this latest data point. The notion of a polling recovery for the government is no longer as clear as it was prior to receiving the Morgan multi-mode poll.

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