Something interesting has been popping up in the polling with the two party preferred vote – there is a statistically significant difference between the two party preferred estimate when poll respondents get to allocate preferences compared to the two party preferred estimate when preferences are allocated on the same basis that they were at the 2007 election.
We have two pollsters that publish these two different ways of allocating preferences to get a two party preferred estimate – Morgan and Nielsen – and in both cases the same phenomenon occurs. There’s been 72 Morgan polls and 13 Nielsen polls since Rudd was elected, so we have a decent set of data to work with – certainly enough to imply that the polls might actually be a little better for Labor than the published headline results suggest.
UPDATE: Nielsen’s headline numbers use respondent preferences even though they measure both , while Morgan and Newspoll use 2007 election preference distributions.
First up, if we run the ALP two party preferred results of each pollster using the two metrics, we get:
In both cases, the ALP two party vote is consistently higher when respondents get to allocate preferences than when we use the preference distribution of the 2007 election. It’s worth pointing out that the ‘headline number’ used when reporting polls is based on the 2007 preference distribution for Morgan and Newspoll, but not for Nielsen.
If we take the difference between the ALP two party results based on how voters say they will allocate preferences and the ALP two party vote based on the 2007 preference distribution for each pollster, it tells the basic story.
If we now transform those raw results into the percentage of time that the voter allocated result is higher than the 2007 preference distribution result, and by how much we get:
Only 12.5% of all Morgan Polls have the ALP TPP based on the 2007 preference distribution higher than when voters allocate preferences themselves (2.8% for one point difference, 9.7% for half a point difference). 19.4% of the time the two measures are the same 68.1% of all Morgan polls had the ALP TPP higher when voters allocate preferences compared to the 2007 preference distribution.
For Nielsen, not one of the 13 Nielsen polls has had the ALP TPP based on the 2007 preference distribution higher than what happens when voters get to allocate their own preferences. It’s also interesting that both pollsters have the same approximate proportion of their polls having a ALP TPP when voters get to allocate preferences rather than using the 2007 preference distribution.
Yet, if we run a scatter and regression on Morgan and Nielsen results where the left axis is the ALP two party preferred poll result based on how preferences were distributed at the 2007 election, and where the bottom axis is the result from the same poll but where poll respondents allocate their own preferences – a noticeable difference emerges between the two.
The dots are the actual poll results, the red lines are the linear regression line of best fit through those poll results and the black lines are where we’d expect the regression line to be were the differences between the 2007 preference distribution and the poll respondent preference allocation essentially random.
With Morgan – the higher the ALP two party preferred vote becomes according to the 2007 preference distribution, the more voters tend to give an even higher vote to the ALP when they allocate preferences themselves. Nielsen on the other hand has a consistent difference regardless of the size of the vote – with 9 polls out of their 13 giving the ALP a two party preferred vote 1 point higher than the published headline figure that’s based on the 2007 preference distributions.
The basic statistics for the difference between voter allocated preferences and the 2007 preference distribution for the ALP TPP come in like this:
The difference between the two TPP measures is, on average, half a point higher for the ALP with Morgan polls and over two thirds of a point higher with Nielsen polls.
The big question here is whether the ALP two party preferred is actually being undercooked a little by using the 2007 preference distribution. If we look at the way preference distributions have been changing at elections for the last 20 years, the ALP is currently on a bit of a preference harvesting upswing. The interesting bit is that the Greens vote basically stood still between the 2004 and 2007 elections (7.2% in 2004 compared to 7.8% in 2007), but the ALP preference allocation still increased – so it’s not just a higher Greens vote that’s causing this Labor preference growth.
Mayhap, the polls are actually a little better for the ALP than the headline figures for Morgan and Newspoll based on the preference allocation at the 2007 election suggest.
28 Comments
Well Poss, if the above is true its certainly an “oh dear” moment for the Libs.
Although i’d love to see it happen, and its what the data suggests will happen, i still cant bring myself to believe that the ALP will get 57 or 58% of the TPP at if an election was called now. Its just too radical.
Still, I also cant believe that the Libs will get any kind of swing towards them. I really wish that the ALP was running candidates in Bradfield and Higgins. That would provide some interesting info on a TPP basis, but without the ALP involved i dont think they those contests will mean much except to the Turnbull leadership debate, and that getting really boring.
All this good news for Labor surely has to be tempered by the fact that the Opposition has to get something right before the election, doesn’t it?
At the moment we’ve got Labor cruising past the finishing post whilst the Opposition is still standing in the barrier-stalls. It is all too good to be true. And, as the saying goes, ‘if it’s all too good to be true, then it is too good to be true.’
I still can’t believe how it is so sickeningly snide of Labor not to field a candidate in Higgins. On the dubious claim that it would be a strain on their finances. Bollocks! All Governments spend our money as if there was no tomorrow. Thanks to the new Greens candidate and to Higgins being a sure-fire Liberal seat; shall I suggest, a too difficult to win seat, they probably think it would bad for public relations to take too much of a thrashing.
Indeed, there are quite a few Higginsites-apologies for my made up word-who would love to vote for a Labor candidate. We have been short-changed. Poss, do you agree?
2
Venise, The Labor Party is referring to their own private funds, not taxpayer dollars.
There seems to be a reasonable underlying logic to this observation. If a party becomes more popular, you’d expect a rise in both the primary vote, and the proportion of minor party voters who’d prefer them as their second choice. Actually it seems a little odd that pollsters would use the last elections preference allocations to come up with the TPP? (although while the difference appears statistically significant, it is relatively small).
Venise,
Don’t put your house on it.
venise – for the Libs to get anything right would be against the run of play.
Unless there is a beachball on the pitch, or an own goal, you’d have to write them off given that it’s now well into the second half.
I’ve always suspected that prefs from minors, Greens in particular, would flow more heavily to Labor at the next election. This was merely an assertion on my part – and we all know about assertions. But I’ve been surprised that this possibility hasn’t had an airing before now.
Well done Possum.
In surveys, minor parties receive some protest votes. Protest votes are from disenchanted supporters (of the Govt of the day). Disenchanted supporters, on the day when it Really Counts, will strongly return to their natural persuasion. LNP benefitted in 2007 (and earlier). Labor will benefit in 2010.
So this isn’t a Labor artefact per se – although Labor is the beneficiary this time. It is just that Pollsters need a mechanism to avoid wild fluctuations in small vote areas and using the last election proportions is as good a way as any.
But it comes a bit unstuck when there’s a change of Govt.
Possum, is there any data from earlier to confirm (or disconfirm) this?
Nipper @ 7
Actually, that was my initial thought – that the surveys over-estimate the “independent/other party” vote – partly because not every electorate has an independent or other party candidate and partly the protest vote scenario. But when I compared the vote at the last election and the current survey estimates for independent/other party they match pretty well. So it doesn’t really support the hypothesis that this is an simply Labor voters expressing discontent with Labor in surveys.
I think he reason that pollsters use the previous elections preference distribution is that it works – most voters follow the card.
However, the trend to Labor in the preferences of minor parties/independents is rather interesting.
I’d be interested to see a similar analysis of the polls pre the 2004 election.
The reason pollsters prefer to use the previous election estimates is that it tends to work better. In 2004, both Nielsen and Newspoll switched to asking the question on preferences. Both companies got the primary votes close to correct, but both had 2PPs that inflated the Labor vote because the preferences flows to Labor in their polls were stronger than occured on election day.
In the past when Morgan has published minor party preference breakdowns, the Green preferences always come out at 90% to Labor and they usually come out at 70-75% at the election. One example of the poll not getting the same finding as election results.
Newspoll continues to ask the preference question close to election time, and continue to find it produces a higher Labor 2PP, exactly as Possum finds here. However, it also over-estimates the Labor 2PP compared to the election result. Quite why is not clear, but it is a finding consistent enought to make pollsters think that using past preference estimates is more reliable. It is possible that on the day campaigning outside polling places does make a difference to preference flows, and this is something a phone survey can’t duplicate. Compulsory voting also brings people to the polls who are completely bewildered by the process, and you would be surprised how many people are exit polled and can’t tell you who they voted for.
Of course there are elections where the past election is not a good guide. Given the shift in primary votes from Labor to the Coalition in NSW election polls, it would not surprise me at all if some similar shift did not also occur in preference flows.
I saw Abbott on Lateline last night. His eyes look hollow and he seems to have aged quickly in the last couple of years. Might be time he joined the rest of us in a job outside of politics. There’s likely to be little career advancement ahead for him in his current position.
Possum, this is the good stuff.
Thank you.
Anthony, that’s also the good stuff.
Thank you.
Interesting work Possum. A relatively small effect, but it may well tip a few seats.
On Higgins: There is no gain from Labor running a candidate. They won’t win. The risk is the Labor candidate losing ground to the greens (if the greens are right about public opinion on ETS). Even gaining 5-7% off the Liberals will still leave Kelly with more than 45% of the primaries. In the end, Labor candidate gets trounced by the Lib.
Ghostwhovotes: I think I understand. You mean the money they get as donations?
VP: Rest assured, I vote with my heart, not my money. And my heart is Green with a tilt to the left. Which is why I am fuming about Labor declining to field a candidate in the Higgins by-election. I can’t think the Green’s choice of Clive Hamilton is a stunning selection. I am totally against censorship of the internet. Also the man comes across as being a bit strange. Although he does write well on the environment.
Don’t forget what Possum has said before. Namely that Higgins is losing it’s Liberal infallibility. That had the Labor Party fielded a candidate the Libs could be pressed a little more than in the past, and in 2014 the vote was almost certain to be Labor’s way.
Which is never gonna happen if they don’t even field a candidate.
In the last 25 years, the Liberal margin in Higgins has hardly moved compared to the overall Liberal 2PP margin in Victoria. The 1990 redistribution cut the Liberal margin by 5%, and Higgins has not swung as much from election to election as the rest of Victoria, but once you take account of the 1990 redistribution, Higgins has hardly budged.
Bradfield has seen more Liberal decay over the last 25 years than Higgins. If the trend continues, the Liberal Party will lose Bradfield in about 2050. However, this trend does not take into account what might happen if the polar ice caps melt and there is a flood of refugees into the hillier parts of Sydney’s North Shore.
Antony Green: How depressing. In my five moves of house in my life, all of them have been in Higgins. Different suburbs, same electorate-Higgins. Damn it! Well who am I to argue with you? Cheers
How much has Treasurer Costello kept the Higgins vote under control this past decade.
Thanks for pointing that out Antony. I’d always suspected that Higgins was not a swinging electorate compared to say the middle-outer mortgage belt suburbs. Its not as though there is ever going to be an influx of union members into Higgins.
The interesting thing about Higgins is it’s relative stability -swinging less than nearly all electorates, but moving against the Libs about 1% per election.
You can see it’s slow grinding change using the Electorate Demographic Profile toy.
http://blogs.crikey.com.au/pollytics/electorate-demographic-profiles/
I can’t access your profile toy Possum, but I bet you haven’t accounted for redistributions. You’ll find that the slow grinding change completely disappears if you take account of the 1989 redistribution.
http://blogs.abc.net.au/antonygreen/2009/10/how-safe-is-higgins.html
The toy only goes from 1996 onwards.
It doesn’t actually disappear – it’s still there, around 1% an election on the TPP
I use the ALP as a reference, so in Higgins it goes 39.3, 40.4, 41.6, 41.2, 43
Slow and grinding.
But in the same period the Labor Victorian vote was 50.3, 53.5, 52.1, 49.0, 54.3.
All Higgins has done in that period is what the rest of Victoria has done. The gap was exactly the same in 2007 as 1996 so no relative change.
The gap between the two in 96, and 07 was the same – but during the intervening years it was pretty volatile, moving from under 8 to over 13.
What makes me think that Higgins is moving independently to Victoria is that not only has it acted against the Victorian swing before, but the swing is pretty smooth over time and in the same direction like socio-economically similar seats such as Bradfield, North Sydney, Warringah and Kooyong (although some of those have moved more than others)
Kooyong will be interesting to see now that Petro isnt there – especially if it moves a a couple of points in some direction.
Yes, but the swing in Higgins is smooth compared to the outer suburban electorates where we know the swings are not smooth. You didn’t get a big swing in 2004 because the seat wasn’t mortgage belt and wasn’t affected by the Scoresby motorway. And in a seat like Higgins, the campaign effort by both sides is minimal, so it’s not much of a surprise that seats like that can just drift along. The effort put in to create a swing in some seats doesn’t exist in seats like Higgins.
What you also miss by concentrating on socio-economic variables is the political mileau of a district. The solid tory urban districts might look like their going to swing but they rarely do.
Antony GREEN
“The solid tory urban districts might look like their going to swing but they rarely do.”
Antony, I ssume you’re talking about voting intentions!!
I think the Antony-Possum fight broke the Crikey website
Thomas Paine asks how much has Treasurer Costello kept the Higgins vote under control? Possum would be able to answer that question, but I have always had the feeling that the electorate of Higgins regards any Liberal candidate as ‘their man’. And going on all the marvellous work for the community that Peter Costello hasn’t done. I don’t think it seems to matter.
They are a lifeless lot in large areas of the electorate and come polling day they accept the handouts from people working for the other parties, but their minds are already made up and the leaflets hit the WPBs very quickly.
The areas I’ve mentioned before, Windsor, large parts of Prahran, parts of South Yarra nearest to Chapel Street, parts of Malvern and Armadale were/are the main hopes for a change. But, as yet, it’s hard to imagine the youth vote-from which the Greens might hope to pick up votes-being stronger than a potential Labor candidate.
erk! I just found an old school photo from 1965 – when I attended Hawksburn State School. If we hadn’t moved out – I’d be holding the pencil poised over the ballot paper, and I think I’d have to go for Clive after all.
Very amusing David, and I would have been walking the dogs in the park next to the school.