Possums Pollytics

Politics, elections and piffle plinking

Posts Tagged ‘election’

Chilling Steadiness and Deadly Intent

Posted by Possum Comitatus on November 20, 2007

Don’t you just love that cracker of a line from Peter Hartcher about the behaviour of the polls?

As a new day dawns, the institution of Newspoll Tuesday – campaign edition, comes to a close.

And what new excitement does the Newspoll bring us on this solemn occasion?

None at all – its more of the type of business as usual that Peter Hartcher described so well.

The headline figure gives us a TPP estimate of 54/46, with the ALP down 1 and Coalition up 1 since the last Newspoll.


On the primaries we have the ALP down 2 to 46, and the Coalition up 1 to 41, giving us the following (thanks to George P. again). These results come from a survey of 1696 people giving us an MoE of around the 2.5% mark.


The Greens vote is at their highest level for a long time, at 7 points matching their 2004 election result of 7.2. The non-green minors are stuck on the same 6 points they have been for the last 4 polls.

So Newspoll Tuesday – ‘campaign edition’ ends with the same more of the same that it’s been delivering for weeks.

But the one thing I wanted to show you all today was the long term trend since the 2004 election. If we take the ALP two party preferred vote between November 2004 and November 2006 and run a linear trend using a simple regression through that period, and then we project that pre-Rudd trend through to today – look at what we find:


The ALP two party preferred vote is currently at its long term, pre-Rudd trend.

Now isn’t that interesting.

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Posted in Polling, Voting behaviour | Tagged: , | 25 Comments »

The Polls Have It

Posted by Possum Comitatus on November 16, 2007

Two bits of polling to chew through today, an ACN phone poll and a cumulative Newspoll breakdown.

First up we have a new ACNielsen, with the ALP primary down 1 to 47%, the Coalition primary up 2 to 43%, with the minors and others down 1 to 10%.

The headline two-party preferred results have the Coalition up 1 point to 46 for a 54/46 TPP lead to the ALP.

Not much going on there in terms of movement, with 1465 survey respondents giving an MoE of about 2.6%.

Tracking the primary votes over the longer haul we get this (Ta George):


And a TPP history of this:


ACN since August has had 55/45 being the name of the game, coming down from a 57/43 split in the first half of the year.

There’s not much to look at there, so moving right along to the Newspoll breakdown over at The Oz which was taken either side of the rate rise, but before the campaign launches.

The Newspoll cumulative is based on the last two big Newspolls to give a combined sample of 3402 respondents, giving a MoE on the state breakdowns at about 4%. Here I’ll take the first two Newspolls and combine them into one result, then take the last two Newspolls and do the same to get two different polls that don’t overlap (Newspoll is running a two poll rolling average, but I’d rather distinct pieces of polling data here).

Tracking the primary votes over time we get (where week 2 and week 4 refer to the campaign):



Interesting here is that the WA primary has been on an increasing trend for both parties over the last few months at the expense of the minors vote. The other states are showing a fair bit of volatility with that 4% MoE making it hard to tell what’s really going on if anything. But what is probably certain is that the Primary vote for the ALP in NSW didn’t drop by 5% in 3 weeks (nor increase in Vic by 5% over 3 weeks) – that sort of movement just doesn’t happen that dramatically without something like a leadership change, so there’s a fair bit of noise in the series.

Looking at how this transfers across to the TPP:


This would deliver 99 seats to the ALP in a new parliament according to Antony’s spiffy calculator, which is 9 seats more than the number that a national 6.8% swing would deliver using just the national pendulum.

Qld delivers 13, NSW 7, Vic 9, SA 5, WA 2, Tassie 2 and the NT 1.

Higgins would fall in such a uniform state swing and Goldstein would become the most marginal electorate in the country, being retained by the Coalition by 0.03%.

That would be Howard, Turnbull, Costello and Brough all sacked by the electorate leaving an interesting decision for the Libs in terms of who would be leader.

It’s interesting to see the non-capital city blow out from the capital city swings over the last few months – that’s probably an artifact of the Qld swing on the one hand with Qld being rich in regional seats, and the 35-49 females in NSW city seats on the other, which we better explain with the demographic data.



What stands out here is the movement in the female vote back to the Coalition.

Taking this into account with the state swings, we can probably say that Newspoll was picking up a change in 35-49 year old female voters primarily living in NSW city seats (If I were to make a guess). If there is a bit of sampling error in the polls to explain the big jump in NSW, this looks to be the demographic where it occurred. The 35-49 group has moved 7% back to the Coalition over the last few months, with females moving 5% over the period (males only 1%) and NSW moving 5% over the period as well – all back to the Coalition primary. When you take account of the capital city vs non capital city swings from earlier, it seems to be a metropolitan phenomenon.

In terms of primary vote swing since the last election, as close as we can tell, they look like this:

  Male Female 18-34 35-49 50+
Coalition Primary Swing -4% -4% -6% -1% -6%
ALP Primary Swing 8% 8% 12% 5% 8%

So you can get a bit of an idea of the demographics where the minor parties are taking a hit.

If this female NSW swing is happening (which it may be, just not as much as the data is probably suggesting) it will be interesting to see if the bank notices arriving about increasing mortgage payments makes an impact (especially as surveys suggest it is the female in the family that does the home budget), as well as how the childcare and education policies from each party play out.

As for what’s going on in Victoria – your guess is as good as mine. Those Mexicans have been confusing all year and don’t look like stopping any time soon.

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Posted in Polling, Voting behaviour | Tagged: , , | 40 Comments »

Hi, I’m Kevin and I’m here to make your kids a nerd like me.

Posted by Possum Comitatus on November 14, 2007

The ALP campaign ‘launch’ was today and it’s hard not to miss the policy thrust and vote angle.

Nerds unite – education for all! 😉

450K extra training places including 65K apprenticeships, a computer at school for every child between years 9 and 12, doubling University scholarships to 88K by 2012, doubling post-grad scholarships to 10K and throwing in 1000 beefed up research fellowships.

It’s a beefy education package, and interesting as a play for the vote.

The narrative of the campaign launch is a clever pincer movement trying to turn Howards historical advantage of successfully porking the electorate against him (by making it a negative in terms of it adding to inflation and increasing mortgage payments as a consequence) while simultaneously positioning Rudd as future oriented compared to Howard, and cashing in on the “it’s time” theme.

It’s all very Rovish when you think about it.

We have interest rates (an historical Coalition strength in terms of issue positioning) starting to work against Howard by not only rising in the campaign itself, but coming off the back of a series of rises that basically makes the Coalition campaign theme of the last election look all a little dodgy to the punters.

That ‘dodgyness’ has been exacerbated by the “Howards a clever politician” line that’s been run for 8 months, and now we have Rudd saying that Howard is going to cause your mortgage payments to rise even further because of his pork barrelling in the election.

But “look at me” says Rudd, “I’m not going to risk that, instead I’m going to give your kids a better future” instead of handing out pork willy nilly and making your mortgage payments go up.

So the ALP have essentially covered the full temporal spectrum of the issue neutralisation of interest rates – so to speak.

The “Howards a clever politician” spiel reinforced what people have suspected about Howards political behaviour and framed him and his politics in that negative light. That framing then fed into the recent past with the ALP emphasising the “Keeping interest rates low” claim of the last election. The interest rate rise in the campaign itself has then reinforced the negatives of Howard and interest rates into the present, and now, to top it off, Rudd is pushing with his responsible spending mantra that Howard, in comparison, is going to increase rates again in the future as a result of his porkbarrelling.

It’s all quite audacious really.

Then with the other side of the play, Rudd goes hard on the education issue which plays up the difference between the Rudd vision of skills for the future and Howards vision of the 3 R’s being all you need (which I still cant believe that Howard actually said at the Coalition campaign launch – Textor must be isolated for that nonsense to be allowed to come out of Howards mouth)

Throw in prodigious use of the word “digital”, talk about renewable energy and infrastructure and the juxtaposition becomes powerful.

It’s a pretty tightly crafted trap, and pretty ballsy to boot.

And a guy like Kevin Rudd that looks a bit nerdish can probably get away with it better than most. When he talks about the benefits of education and being an “economic conservative”, the punters believe him because he looks the part. It links Rudd the person to Labor policy and lets the latter feed off the popularity of the former.

Although those Labor types at the launch were a bunch of happy clappers weren’t they?

I know it’s the way with these things, but sometimes there’s probably a limit where the ‘spontaneous’ outbreak of applause becomes a little gagworthy :mrgreen:


Just further thinking about this, what sort of response can the Libs make to “giving kids computers at school and providing more education places”?

It’s a hard policy program to argue against, and the fact that it’s only 25% of the pork that the Coalition went with makes it hard for them.

I’ve just seen Shrek on TV avoiding the education policy and talking about Unions, the potential for recessions in the US and Europe, and unions.

The Coalition might be snookered on this for a few days.


For a real hoot, the Newcastle Herald reckons it has a poll on Paterson with a 0.1% margin of error. To get that, considering Paterson has an enrolled voter population of 90 504, their sample size would have to be a tad over 85 000.

If you want, you can play around with the sample size required here.

Honestly – these guys need to put it back in their pants.

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Posted in spin | Tagged: , , , | 96 Comments »

The race against the cashrate clock

Posted by Possum Comitatus on November 8, 2007

Since the interest rate rise is the news of the week, I thought we might go over the timing issue of how long it takes for a rate rise to flow through.

The big problem here is that the rate rise doesn’t coincide with the polling cycle in a consistent manner, so sometimes polls will be taken a day after the rise, sometimes nearly a fortnight after the rise – and for us here trying to get a statistical grip on whether the rate rise will come through in the next three weeks, well it all becomes a little cloudy.

But first, let’s go to what we do know.

We know that when a rate rise happens, it boosts both the ALP primary vote and the TPP vote, we saw that the other day.

If we use the monthly averages of Newspoll, we can regress the change in that monthly average (if the TPP goes from 52 to 54, the change would be +2 for example) with the change in the cash rate (if the cash rate rises from 6.5 to 6.75, the change would be +0.25 for example). When we do that we find that there isn’t a statistically significant relationship between the change in the ALP TPP vote and the change in the cash rate during the month that the RBA lifts rates. But if we lag the change in the cash rate by one period, where we are measuring the relationship between the change in the ALP TPP vote with the change in the cash rate in the previous month, out pops the following:

Where D(TPPALP) = the first difference of the ALP TPP vote, which is the monthly change in the ALP two party preferred vote
D(cashrate(-1)) = the first difference of the cash rate lagged one period, which is the change in the cash rate in the previous month.


The coefficient on D(cashrate(-1)) is what we are interested in here, and it tells us that when the cash rate lifts by 1 percent, the ALP TPP in the next month jumps by 7 points. So when the cash rate lifts by 0.25 percentage points, the ALP TPP vote increases by over 1.5 percentage points. The t-Statistic and the Prob value tell us that this relationship is highly statistically significant.

The little graph in the mix shows how it plays out, where the black line represents a change in the cash rate in the previous month, and how it plays out with the change in the ALP two party preferred vote. Notice how the black line spikes when the red line spikes? That’s the visualisation of the relationship we are measuring.

So we would ordinarily expect that the ALP would get a boost in December from the November rate rise.

But when we try to bring that resolution of the data down to the poll by poll level, we run into the problem of the polling cycle not being consistent with the RBA cash rate announcements.

If we graph the change in the cash rate (the blue triangles) against the change in the ALP TPP using every Newspoll since the last election we get:


As you can see, when the cash rate changes, sometimes the ALP vote goes up with it, sometimes the ALP vote goes up the next poll and sometimes the poll after that.

The problem here also, is that there is a fair bit of random movement (sampling error) that might be polluting the monthly change in the ALP TPP vote that can’t really be cleaned up unless we use something like monthly averages.

So the big question becomes whether or not the election campaign compresses the reaction time of voters when it comes to a change in the cash rate?

Let me state to begin with that I don’t believe a word of this guff about how interest rates will shift the focus back to the economy and that will somehow benefit the Coalition. I’d like to see some evidence of that proposition, and the Newspoll “better economic managers” results aren’t evidence as there’s no statistical relationship between the Newspoll economic management question and the Coalition vote at all, and only a small, marginal relationship for the ALP.

The big question based on the actual historical evidence is one simply of time – a lack of it for the ALP or just enough for the Coalition.

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Posted in Leading Indicators, Polling, Voting behaviour | Tagged: , , | 87 Comments »

You tell me which is more likely?

Posted by Possum Comitatus on November 7, 2007

Rates are up. You tell me which scenario is more likely?



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Posted in Leading Indicators, Voting behaviour | Tagged: , , | 87 Comments »

Why it’s all about John

Posted by Possum Comitatus on November 6, 2007


This was me in Crikey yesterday.

Since February, the Coalition political strategy has played out on the ground as an attempt to focus attention on Rudd. Whether this has been more by accident than design is probably worth pondering as well, but for all the “look at Kevin” programs, not a great lot has been achieved.

From Rudd dining with Brian Burke , his childhood memories, his links to those union blokes that keep turning out the lights, right through to actual policy programs like education, environment and infrastructure initiatives (that we now know, courtesy of the infamous Crosby Textor Oztrack 33, actually worked in the Labor’s favour by highlighting issues that the ALP had position dominance on) – the strategy that actually played out on the ground was one of focusing attention on Rudd.

Yet for all those attempts at focus shifting, and for all electoral diversional therapy involved, the key measures that matter continue to be intimately linked to the performance of John Howard himself.

The Coalition two party preferred result continues to be intimately linked to Howard’s satisfaction rating since the 2004 election.


A few quick regression equations and a granger causality test on the relationship between these two series suggests that it is the change in PM satisfaction levels that leads to changes in the Coalition two party preferred vote, rather than the two series moving together as a result of third party influences.

The punditry may say that Howard is still extremely popular considering his satisfaction ratings, but with his satisfaction ratings being so intimately linked to the Coalitions TPP vote, that line of thinking quickly becomes a bit a grand non-sequitur in the general scheme of things. His satisfaction only needs to fall small amounts to have a serious impact on the Coalition vote.

The other key measure intimately linked to Howard’s performance is the ALP primary vote via the PM dissatisfaction rating, as we hinted at last week.


Again, after a few quick regression equations and a granger causality test on the relationship between these two series, it is the change in PM dissatisfaction levels that leads to changes in Labor’s primary vote, rather than the two series moving together as a result of third party influences.

What is also interesting to note here is the gap that has recently opened up between these two measures, suggesting the possibility that Rudd is starting to gain support as a result of what the ALP is actually doing, rather than simply relying on dissatisfaction with Howard to deliver them electoral support.

So while all the policy noise and political advertising fills the political brainspace of the nation, when it comes right down to it, this election is still all about John Howard.

The big danger however is that hint in the last chart that suggests that Labor might finally be gaining support on the basis of their own merit. If that relationship starts to consolidate, there will be very little that Howard can do to turn his electoral fortunes around. When you are staring down the barrel of electoral annihilation, that is probably the last thing he wants to hear.

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Posted in Crikey, Leading Indicators, Polling, Voting behaviour | Tagged: , , , | 4 Comments »

SA and the Census Data

Posted by Possum Comitatus on November 5, 2007

SA and the Census Data

Continuing on with our series of combining the Crosby Textor Oztrack 33 swings to the demographics of individual electorates by State, today we’ll have a look at little old South Australia.

So first up, we better have a look what Crosby Textor had to say about the swings in SA:


The big demographic swingers in South Oz apart from parents were part-time workers, the 18-24 age group and the 35-49 age group.

So let’s have a look at how these play out seat by seat, and we’ll use the following:

“18-24” is the number of 18-24 year olds in the seat as a proportion of all people in the electorate aged 18 and over.

“34-49” is the number of 34-49 year olds in the seat as a proportion of all people in the electorate aged 18 and over.

“PTW” is the number of part- time workers as are a proportion of all people in the electorate aged 18 and over.

“HA” is the percentage of the median household income that would be required to make the median home loan repayment for the electorate. This gives us a measure on housing affordability.

“LwUb” measures the number of Lower White/Upper Blue collar workers in the electorate as a proportion of all people in the electorate aged 18 and over. This is the demographic that is having the largest negative experience of Workchoices.

SLA1+ and SLA5+ are the proportions of the electorate that lived in a different statistical local area 1 year before the 2006 Census and 5 years before the 2006 Census. This gives us a bit of an idea of the overall population change of each electorate.

Again, we will just look at the Coalition held seats, and the data is based on the current electoral redistribution.

The current margins of the seat are:
Barker (19.9%), Boothby (5.4%), Grey (13.8%), Kingston (0.1%), Makin (0.9%), Mayo (13.6%), Sturt (6.8%), Wakefield (0.7%)

Seat 18-24 35-49 PTW HA LwUb SLA1+ SLA5+
Barker 9.77 29.54 18.44 27.21 24.49 7.11 20.47
Boothby 11.97 26.09 20.33 29.38 24.49 10.65 28.88
Grey 9.4 28.73 16.99 25.88 22.64 7.1 19.94
Kingston 12.49 29.38 20.26 27.76 31.84 9.88 27.07
Makin 12.47 29.14 19.36 25.46 33.47 8.97 26.08
Mayo 9.81 30.06 22.12 27.11 26.62 8.67 27.63
Sturt 12 26.48 18.76 30.07 24.57 10.79 28.59
Wakefield 12.7 30.3 17.02 29.22 26.53 10.24 28.6
SA Average 11.92 28.29 18.64 28.71 26.31 10.13 27.31

What strikes me about the Coalition held seats in SA is the remarkable blandness of them all. They have the same rough proportions for everything.

The young population is all within 3%, the 35-49’s all within 4%, Part time workers all within 5%, housing affordability all within 5%, Lower White/Upper Blue we finally have a bit of variation at 11% but this wasn’t designated as a key demographic in South Australia by CT. Everything seems to be all very uniform.

So let’s rank them now in terms of which seats would be more likely to swing based on known demographic issues. What we’ll do is take the difference between each measure and the State average. That way, those seats with a higher proportion of swinging groups will have a positive rating, and those with a smaller proportion of swinging groups will have a negative rating. Then we’ll add all the ratings (what are merely the individual differences from the State averages) together and see which seat would be expected to swing the most.

Seat PT diff HA diff 18-24 diff LwUb diff 35-49 diff Total
























































This suggests that Kingston should swing the most based on demographics, while Grey should swing the least based on these demographics. However, this flies in the face of what we’ve heard about in places like Grey, where a large swing seems to on.

Unlike QLD where the swinging demographics of the CT research explained a lot of what we’ve been seeing and hearing about on the ground, in SA it explains either very little at all and local issues are a large player, or the swing in SA is very uniform.

If it’s uniform, and with a 12.4% swing on at the moment according to last big Newspoll, the member for Barker might be the only one breathing easy (although I’d imagine Dolly Downer is as safe as houses as well).

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Posted in Polling | Tagged: , , , , | 14 Comments »

Bring Out Your Dead

Posted by Possum Comitatus on November 1, 2007

Today we have the quarterly Newspoll you have when you aren’t having a quarterly Newspoll – a sample of 3413 voters taken over the last fortnight, broken down into States, city type and demographics.

The State breakdowns have an MoE of around 4%, the age breakdown around 3% and the capital city vs non-capital city 2 and a bit %.

So let’s take the longer view first, looking at the behaviour of the States since the lead up to the last election, and where the entry for the 4th Quarter of 2007 is todays Newspoll results.



Since the last quarterly breakdown we’ve seen Victoria come back to the fold a bit for the Coalition, Qld moving solidly to the ALP and WA moving a tad to the ALP. But considering the MoE on these things, it looks like we have 4 states bunched up around an ALP primary of near 40 50 (bloody hell, how’d I do that), and WA down around the very low 40s.

The Coalition though is stuck down around the high 30’s and low 40s everywhere except WA. No election is going to be won with those low primaries.

Next up we’ll look at the demographics over time:


Slight movement to the both parties on the primary vote here is the name of the game, with the 18-34 demographic being the biggest mover, with a 4 point jump to the ALP. Maybe noise, maybe not.

Now for the swings.

First up, primary vote swings by State:


Qld – Yikes!

Not that NSW or SA are particularly pleasant for the Coalition either. I reckon the Qld number is a bit too big and the Vic number a bit too small considering what I’m hearing on the ground in both places.

On the demographic front we have:


There’s two big movements here of interest. Firstly the 6 point decrease in the minor party vote that’s gone to the ALP in the 35-49 age group. The other is the 8 point decrease in the minor party vote in the non-capital cities that has flowed to the ALP primary. If that holds, that would have to be a lot of the hippy green and rural/regional independent vote moving across, net, to the ALP.

And finally the big one – the TPP swing by State:


If this were repeated on election night, it would lead to around a 42 seat gain to the ALP and 102 ALP members in Parliament.

Qld alone would, should these state swings be uniform, deliver the ALP government with 17 seats falling up here. NSW is next on 14, then SA on 5, WA on 2, Tassie on 2, NT on 1 and Vic on 1.

Elsewhere the exceptional Mr Meganomics has a great article on some Newspoll data in terms of actual numbers of people over HERE


You can see the results of this in terms of which seats would go by visiting Antony Greens spiffy election calculator, with the results pre-linked in HERE

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Posted in Polling, Voting behaviour | Tagged: , , , , | 81 Comments »

Why Rates Matter

Posted by Possum Comitatus on October 26, 2007


Me in Crikey yesterday HERE

And below:

Yesterdays post “Rates of Gloom” was actually a more in-depth spin-off of this post, so for those of you struggling to follow the stats, this should make everything a lot clearer.

In Rates of Gloom we just modelled the relationship we see below, but also accounted for the effect of leadership changes (the leadership dummy variables) and the honeymoon period that both leadership changes and interest rate rises enjoy (through the time trend variable). Just as the leadership changes of Latham and Rudd increased the ALP vote before it declined from that peak slowly over time as the honeymoon ended, so to with an interest rate rise. After a rate rise, the ALP vote moves up, but then slowly over time it pulls back slightly. There are more complicated ways to model that type of behaviour, but the time trend variable did the job adequately.

So if you read this post first and keep the above in your thought orbit, for those of you not big on the stats side of things it should make Rates of Gloom a bit easier to follow.


With interest rates and widespread navel gazing about the political consequences taking up the media-space, today instead of picking the verbal lint from our bellybuttons over the issue, how about we go to some spiffy little charts that sum up perfectly the millions of words that will be written over the next month.

First up, let’s run the RBA cash rate against the PM dissatisfaction rating over the period 1999-2007, using Newspoll monthly averages for the latter:


Now how is that for a snazzy little leading indicator!

Next up we’ll run the cash rate against the Opposition primary vote over the same period using Newspoll monthly averages:



One word sums that up – Ouch.

Now for the relationship between the Opposition primary vote and the PM dissatisfaction rating:


And that sums up the debate – three graphs are worth a million words.

The only question becomes whether interest rate increases lift the Opposition primary vote directly, whether it increases the Opposition primary vote via PM Dissatisfaction or whether it works via both channels?

As far as the Coalition is concerned however, it’s probably a moot point.


I was just informed of a pretty spiffy site:

Soapbox is a unique Australian political archive of
federal elections, bringing together key historical documents and
audio-visual material, and making them available to students, researchers,
journalists and the general public.”

It’s a cracker of a site if you are into historical election material. Very, very, very much worth a visit:


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Posted in Crikey, Leading Indicators, Voting behaviour | Tagged: , , , , | 65 Comments »

Rates of Gloom

Posted by Possum Comitatus on October 25, 2007

It’s equation time!

So how important is the cash rate on the Oppositions primary vote?

We’ve modelled this before over here in terms of the effect a rate change has on the primary votes of major parties and how long it takes for that effect to flow through, but today we’ll take a different approach entirely.

What we’ll do today is make a simple model that can explain the effect (if any) the cash rate level has on the ALP primary vote by taking into account the ALP leadership and any linear time trends that may be floating around in the mix.

So to start with we’ll be using the period from 1999 through to the present, and the basic model we’ll be looking at is:



ALP = the ALP primary vote at time t (where t is the month).
Cash Rate = the RBA cash rate at time t.
Time = a time variable that has a value of 1 in January 1999, 2 in February 1999 etc right through to its current value of 106 in October 2007.
DummyRudd = dummy variable which has a value of 1 for the periods of the Rudd leadership and zero for all other times.
DummyLatham = dummy variable which has a value of 1 for the periods of the Latham leadership and zero for all other times.

So what we are modelling here is how value of the cash rate explains the level of the Oppositions primary vote, but where we also account for the two leadership periods of Latham and Rudd having an effect, as well as allowing for a linear trend to manifest in the vote.

Once we run the regression model, our results come out as:


Which, for the non-geeks can be visualised as this:


[Note: I’ve ignored the autoregressive nature of the polling series so that the results can be better visualised for the non math-geeks here]

The “Fitted Primary Vote” in the graph is our modelled vote based on the regression equation.

So what to make of it?

For every 1 point increase in the cash rate, the ALP primary vote increases by 3.5 points. So if rates were to rise by 0.25 in November, the ALP primary would be expected to rise by 0.9 points, or around 1 point.

It also suggests that the Rudd leadership (or what has happened during the period of the Rudd leadership) has boosted the ALP primary vote by around 8 points, and that Latham boosted the ALP primary vote by about 2.5 points (which is fair enough considering that Latham took over from the dire polling position Crean had created).

All up, our variables explain about 75% of the movement in the ALP primary vote over the period 1999 through to the present.

If we now run the equation again, but this time using the ALP two party preferred vote, remove the time trend variable and use the period from December 2002 through to today (simply because my TPP figures before that are in a database that I’ve stuffed up and need to rebuild 😉 ) we get:


This gives us a visualised model of:



Again, our variables here explain about 75% of the movement in the ALP two-party preferred vote, the cash rate has nearly identical influence on the TPP here as it did to the primary vote in the first equation, Latham again lifted the TPP vote about the same as he lifted the primary, but this time the Rudd leadership has increased the TPP vote only around 3.5%. This is expected as remember the ALP TPP had been growing constantly since the last election, it was their primary vote that got the big boost under Rudd.

So all up, if rates rise by 0.25 points, the ALP can expect their primary vote to increase by about a point, and their two party preferred vote to do likewise.


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Posted in Election Forecasting, Voting behaviour | Tagged: , , , , , , | 51 Comments »