Two big polls out today – a Galaxy via the News Ltd tabloids and a Newspoll via The Oz. The top line info on the vote estimates come in like this
I’m not sure if this Galaxy was taken over the 24th and the 25th, or just the 25th – so we’ll leave a little asterisk there until we get the info.
Last Newspoll we suggested that the 55 ALP two party preferred was a little overcooked, so there’s no surprise that it came back to the field this week –after all, it was expected to do this very thing. How do we know it was overcooked? Because the deviation of that poll from our trend was too large.
On the other hand, we said that the last Galaxy – the 50/50 TPP result from July 17/18 – was undercooked for the same reason. This Galaxy, like Newspoll, come back to the pack.
The only odd thing about today’s polls, and it is particularly odd, is the gender breakdown of the Newspoll result. Last Newspoll the ALP primary of 42 came from a Male/Female gender split of 39/44. This Newspoll, the ALP primary of 40 comes with a gender split of 39/40. No other polling of late that releases gender breakdowns – from national polling to individual seat polling – has shown anything like this in terms of the absence of a gender gap – so keep that in your thought orbit for this Newspoll. Who knows – it might be a first mover on the disappearance of the gender gap – but it’s not particularly likely.
On our trend estimates, with all the hoo har over Newspoll today you’d be forgiven for thinking that there has been a substantial swing to Abbott over the past week. However, far from our Pollytrend showing a decrease in the Labor two party preferred vote after today’s info has been plugged in, it has, in fact, shown a slight increase – up from 53.2 to 53.6.
To see why, it’s helpful to first take a superficial look at our phone pollster trend in the context of the individual phone polls that make it up:
As our phone pollster trend attempts to look through the poll by poll noise (and the day by day commentary surrounding it – ugh!) , the individual poll results will be distributed somewhat evenly around our trend line, as you can see from that chart. If we zoom in to that trend and look at how each pollster has been travelling against that trend, it starts to make a bit more sense (click to expand):
Even though this Newspoll had the ALP TPP reducing, Newspoll is but one poll – no more, no less. The Galaxy had the TPP increasing, the last Morgan phone poll had it increasing and the last Nielsen had it increasing. Since our trend line not only pays attention to the individual poll results aggregated together, but also the first derivative of those aggregations (or the change in individual poll results taken together), the balance of movement over the last 7 days has continued to slightly increase the ALP two party vote.
The trend line at the moment is however showing a predisposition towards tapering off sharply. If we assume all the pollsters are currently correct and the only reason they are showing different results is purely from the sampling error contained within each survey – we can simulate another arbitrary number of polling results over the next week under the assumption that the polls haven’t changed, and the trend line would taper off sharply to around 53.5%
That isn’t always the case mind you – if you go back to April/May, the trend showed a predisposition to dive sharply and if we simulated polling results from mid April through to early May, the trend was showing a predisposition to dive down to 49%. But the polling came back up to the trend line (as it nearly always does over any arbitrary period because public opinion change nearly always suffers from momentum overshoot).
Our trend line effectively pushes against that momentum overshoot – which is why it has been sitting slightly below the phone poll average since Gillard became PM. In fact, after today’s polls, this is the first time that our phone poll trend measure has actually sat higher than the phone poll average – with the trend sitting on 53.6% and the phone poll average sitting on 53.4%
Meanwhile, the usual Newspoll charts came in like this: