Over the last 30 years or so, probably longer, the size and distribution of the informal vote that we see at every election can be largely explained by a handful of variables – with the election on Saturday being no exception.
The first of these variables is ballot length – the number of candidates we see standing in each electorate. The mechanics of this one are fairly obvious, where a given voter is more likely to make a mistake filling out the ballot when there are say, 13 candidates on the ballot paper then they would if there were only, say, 3 candidates on the ballot paper. The more candidates there are on the ballot, the more human input there has to be to fill in the ballot, meaning the number of mistakes increases. On Saturday’s election, the number of candidates on ballots ranged from a lowly 3 through to a high of 11.
The next variable is a language and communications one – the proportion of each electorate that speaks English poorly or not at all. The mechanics of this one are fairly obvious as well, where folks that may struggle to understand the instructions for filling out the ballot because of language barriers, generally tend to make more mistakes, deeming the ballot paper informal. The proportion of the electorate that speaks English poorly or not at all ranges from a low of 0.1% in the seat of Bendigo in Victoria through to a high of 15.9% in the seat of Fowler in NSW.
The third variable is a political systems variable – Optional Preferential Voting operating for state government elections. What we see happen here is that voters in states like NSW and Qld which have optional preferential voting at the state level, (too) regularly mark their ballots in the Federal election as if optional preferential voting was also applying there. So we witness relatively large numbers of ballot papers in NSW and Qld with just a “1” placed next to a candidate and no further preferences marked on the paper, deeming the ballot informal.
If we use the AEC data at the seat level, we can get candidate numbers and the size of the informal vote for each electorate, while census data can tell us the proportion of each electorate that speaks English poorly or not at well. On the optional preferential voting variable, we can use a dummy variable to denote electorates in states that have OPV operating at the state level (NSW and Qld). With this data, we can do a bit of regression work to explore it.
What we do is regress the informal vote against the other three variables to see how much each variable affects the size of the informal vote. For the stats types, the stats output comes in like this (click to expand):
For the non-stats types, the stuff above looks much more complicated than it actually is. This is what the results actually mean:
NES (non-english speaking background) is the census estimate of the proportion of the electorate that speaks English poorly or not at all. The regression results tell us that for every 1% increase in that proportion of people in a given electorate that speak English poorly or not at all, the average increase in the size of the informal vote in that given electorate is 0.43%. So a 10% increase in the proportion speaking English poorly or not at all would lead, on average, to an increase in the informal vote of 4.3%. It’s a fairly powerful relationship, which we can see by running a simple scatter plot for all 150 electorates:
The Candidate Number results tell us that for every additional candidate on the ballot paper, the size of the informal vote jumps by over 1 tenth of a percent – so having 5 more candidates would increase, on average, the size of the informal vote by 0.65%, or well over half a percent.
Finally, if a state had optional preferential voting operating at the state government level, the size of the informal vote in those states (holding other variables constant) is, on average, 1.65 – meaning that electorates in those states have an informal vote 1.65% higher on average than electorates on states without OPV operating at the state government level.
These variables are all statistically significant and together explain around 54% of the variation we saw in the informal vote on Saturday.
Finally, the “C” in the stats output is the Constant – telling us what the average level of informal vote would be were these other 3 variables all theoretically zero, in that OPV didn’t operate, everyone spoke English well and there were no candidates on the ballot. Some of that might sound a bit silly, but the Constant gives us an idea of the generic level of informal vote that cannot be explained by the three variables.
It’s also worth looking at how the informal has changed since the last election. First up, the broad changes in state and national averages :
The informal vote everywhere went up, with the ACT leading the way with a 2.4% increase while WA showed the smallest increase of exactly 1%. More interesting though is if we compare the regression results above with the same regression undertaken on the 2007 results. For the non stats types, the numbers above (0.43 for NES, 0.13 for Candidates and 1.65 for OPV) are called regression coefficients. We can compare how they’ve changed from the last election:
The NES coefficient increased from 0.308 in 2007 to 0.433 in 2010, meaning that speaking English poorly or not at all had a slightly larger effect this election than in 2007 – which is interesting to think about. It wasn’t a large increase, so it’s probably nothing to lose too much sleep over, but it’s still interesting non-the-less and probably large enough to warrant some further analysis.
On ballot length this election, the size of the impact that candidate numbers had on the size of the informal vote decreased significantly. There are two good explanations for this. Firstly, the number of total candidates standing in this election was much lower than in 2007. Comparing the two we get:
The other factor is a bit more complicated, in that the effect of ballot length on the informal vote is only approximately linear. It is actually more accurate to spec it out in the regression equation as candidate number squared. This is because the marginal complexity of each additional candidate being added to the ballot paper is non constant. The informal vote increases more when the candidate number jumps from, say, 8 to 9 then it does when it increases from, say, 3 to 4.
So having a smaller number of candidates this election easily explains the significant drop in the power of the effect of ballot length on the size of the informal vote.
Some people disagree with this non-linear specification of ballot length – but it’s about 5 elections in a row now where non-linear specification of ballot length generally produced not only more robust results, but one with higher explanatory power as well. We’ll do a Nerdy Sunday post on this when the election results are finalised to get deeper into it, as well as how the NES variable actually behaves in the same way – which has interesting things to say about community dynamics.
On the OPV variable, this election saw a sharp increase in the average size of the informal vote in electorates that have OPV at the state level – up from an average increase of 0.94% per electorate in 2007 to a large 1.65% this election.
That is a large jump.
We really need to think about the interaction that OPV at the state level has on the size of the informal vote on our federal elections. 1.65% is enough to change the results in a dozen seats and it’s been clear for a while that the different regimes at different levels, increases the size of the informal vote to the point where it probably makes a material difference on federal election results – in an election like we had on Saturday, it is probably large enough that it may well have delivered a different government.
Finally, it’s worth noting the changes in the Constant and the R-squared. The R-Squared tells us how much variation in the dependent variable (the size of the informal vote) can be explained by the variation in the independent variables (NES, Ballot Length and OPV). On the R-squared, the three variables explained approximately the same amount of variation in the size of the informal vote as last time.
The Constant, however, more than doubled – up from 1.26 in 2007 to 3.08 on Saturday.
This suggests that things other than these variables we analysed here increased the size of the generic informal vote – near doubling it. Mark Latham might yet have something to answer for.
52 Comments
Possum, I suggest you add a variable relating to education levels.
I’m planning on taking a further look at this in another post a little later on. Education is a difficult variable to deal with because it geographically correlates with NES electorates.
If I add the census variable “Proportion of the electorate with a year 10 education or less” into the equation above – it suggests that for every 10% increase in the proportion of electorate with a year 10 level of education or less, the informal vote increases by 6 tenths of 1 percent. So it doesn’t have an effect as large as we might think – but also gives us collinearity in our equation as it correlated (inversely in this case) with NES
[This is mainly academic but...] if the variable you’re using for NES is from the census and reflects the population of residents rather than electors than the electorates with high NES proportions might be a mix of those with large proportions of eldery post war migrants and those with large proportions of recent migrants. Since the latter would have a lower proportion of citizens (and thus voters), it’d be interesting to see if there was any heteroscedacity there.
Richard – it’s a good question. The census has a few questions on this, from persons born in non-english speaking countries through to persons speaking a language other than English at home – and they all throw up pretty similar overall results.
On the one hand that’s pretty understandable since they’re all intimately intertwined events anyway, but on the other, neither is exactly what we’d be after to make a more robust estimates of just voters.
I did some analysis on the 2007 election result using, I think, NES aged under 45, and it remained pretty consistent from memory.
It’s probably worth playing around with a little more though.
Possum, isn’t the OPV thing likely to mask other reasons for informality because NSW and QLD, as you showed in the last blog, also have the worst performing labour/state governments, and therefore, perhaps, the people most likely to write “screw you all” on the ballot or some such? Could you do a regression on Informality vs popularity at state level as you did last post for the federal vote?
James – historically OPV has always made an impact on the level of federal election informals for as far as I can go back. The increase in the size of the coefficient for OPV is probably where the state Labor issues come out.
The informality vs popularity idea thing is a good idea! I’ll have to think about it for a bit though – the results are intriguing
Thanks Poss, very interesting. I think the large increase in informals in NSW and QLD is unmistakeable as a form of protest vote. ACT too, with the best educated population in the nation, and no OPV, also shows a marked jump upwards.
You could remove colinearity between the variables by regressing the principle components. Probably gets a little trickier to explain in a blog though.
El Nino, you think?!
Do you know if the AEC keep any kind of count of the type of informal votes received? I can imagine a few broad categories:
* Blank (which would include the ‘Vote 1 Chuck Norris/No Dams’ types as long as the boxes themeselves were blank)
* Insufficient numbers specified (OPV style)
* Duplicate numbers or non-numeric characters used (e.g. ticks and crosses)
* Illegible
* Other
Whether or not this info was made public, it would surely be valuable info for the AEC and policymakers.
Could you replace the NES with the My School ICSEA and then do a per booth analysis?
More data points it good, right?
Hi Poss,
In Cowper which is one of the poorer and less educated electorates. The Greens were handing out a HTV which did not have a facsimile of the ballot paper but just a 1 in their candidate square. On the back, as the volunteers kept pointing out, was a little essay on what preferences were and how they were distributed – wonderful reading while waiting in the queue.
My thought was that as NSW state elections are OPV – a significant number of informal votes would have be 1 green without other preferences. I know the AEC report will eventually make a comment on this but in the meantime is it possible to compare the informal votes between electorates where the Greens advised on preferences and those where they did not.
Love your work – not bad for a Taree boy.
Possum
Welcome back. Hope you are refreshed. Liked the stuff on informals. I remember an article on this in about 1967 (yikes!) Do you know if anyone has done some useful work on absent, prepoll and postals. I kind of think that up to 20 000 votes in some electorates might not break the same way as all of the ordinary votes but maybe this is wishful thinking. The provisionals BTW probably include some of the GetUp beneficiaries?
The last time there was a general increase in the informal vote, in 2004, the research on the ballot papers revealed there was a general lift in the number of blank ballot papers across all electorates. The assumption was the blanks were probably a protest. The number of blanks declined substantially in 2007. Disaggregating informal vote into numbering errors and other forms of informal voting would provide a clearer picture of the relationship but the data is not currently available.
We also know that the Senate ballot papers induces ’1′ only votes, as shown by my past research on Victorian elections before and after the new Legislative Council ballot papers were introduced in 2006.
The NSW Senate ballot paper was extraordinarily large and I don’t doubt played a part in the NSW informal vote rise.
Bogdanovist – that data has been made available after every election since 1984 and the state electoral commissions all do the same thing. There’s no shortage of researchg data on the subject.
Oakeshott Country went:
Ahem… Wingham
The states of OPV have also traditional Labor support that is most disenchanted.
And state Labor is also most on the nose in OPV states.
The LFV (Latham Factor variable) would also likely be strongest in one if not both of those states.
ie is LVF > OPVNSW and OPVQL> LVF?
And what % of IV is blank vs BL and NES?
QED?
What about correlating the informal votes against the difference between the
number of received votes and the number of people on the electoral roll for
each seat (ie the people the AEC will be sending “Please Explain” mails to).
I am so sorry, please forgive me – what a faux pas!
Ballot length, NESH and OP state are the big predictors of informality. You can get a little bit more explained variation with percent of the electorate with a tertiary degree, and maybe interactions of some of these things (e.g., NESH by ballot length, OP by NESH).
This has been true every time anyone has looked at this.
e.g., my 2007 go at it: http://jackman.stanford.edu/blog/?p=543
2004 analysis: http://jackman.stanford.edu/papers/download.php?i=25
Surely the state OPV/Senate issue is a good argument for OPV at the Federal level, or ATL being applied to Reps ballot as well as Senate?
As insignificant as the numbers would be, I found it interesting when I kept finding blank ballot papers amongst the how-to-vote cards while collecting them from the bins for re-use on election day. They were only lower house ones, I guess the Senate ones were too big to “smuggle” outside.
Perhaps someone in my booth wasn’t paying attention to ensure that the punters were putting their ballots in the boxes!
#22 – doesn’t the booth returning officer have to do a balance at the end of the night and explain a deficiency between issued and counted ballots?
The Hare-Clarke electorates (ACT and Tasmania) have a form of partially-OPV. You don’t have to number every box, but you have to number a minimum (eg number at least 7 in Molonglo).
#23 – Yes, the OIC (officer in charge) does have to do a balance not sure that they “explain” it though. In my booth we were short two Senate papers, don’t know about the Reps as I was balancing Declaration votes at the time. Suppose it is better to be short than over! (which brings on banana republic ballot box stuffing imagery…)
Interesting info about informals in the ACT. I was a polling clerk (first time since 1983!) in a large ACT booth, and I was surprised not only at the number of informals but their composition. I’d estimate at least 2/3 of the informal votes I saw were deliberate, and a high proportion of those were blank. I think the Latham factor was a big one.
Copied from the Crikey website and corrected, thanks to Antony Green (#15 above):
I was hoping for a discussion of the dozen or more seats with the highest informal vote. They all came from NSW. A cursory comparison of this election’s return Vs the last election, in 2007, indicates that the same people, under the same circumstances (thus one does not need to consider NES or OPV factors) have increased their informal vote significantly.
Adjustment for the number of candidates might explain, say, a 26% increase in informals if the candidate number this time was 2.0 above 2007… Poss can do the numbers better than I.
These people have demonstrated in 2007 that they can deliver more formal votes, but have chosen in 2010 not to do so.
The thing which statistics will not demonstrate is the reason for these individual decisions not to record a formal vote. I suggest:
“A pox on all your houses.”
“Don’t want Lib, Don’t want Labour, Don’t know the others.”
The Latham factor.
A handle on this last might be possible by comparison of the blank votes between elections.
I really enjoy what you write here, very fresh and smart. One issue though, I’m running Firefox on Linux and some of your site structure are a little wonky. I realize it’s not a common setup, but it is still something to keep an eye on. Just giving you a heads up.
http://mychinaviews.com
vane – I’m running Firefox on Ubuntu Linux and it picks up the site fine. What problems are you experiencing?
I agree with John Bennetts. I think there was probably a significant intentional factor in the informal voting this time, rather than all the accidental factors described above. I believe Tammie Fraser is probably one of the best known Australians said to vote informally these days.
Antony says
And i can’t believe no one’s yet pointed out that, once again, it’s all Mark Latham’s fault
With all major parties in this election adopting positions against migration, both legal (the “big Australia” debate) and illegal (“stop the boats”), it would be reasonable to assume that voters with NES backgrounds would be more inclined to deliberately vote informally for this election, which could explain the increase in the NES coefficient.
The OPV issues have already been touched on, but OPV happens to coincide with states where disillusion toward Labor has been the greatest this year.
Therefore the 3.08 intercept figure, and subsequently the 1.82 change figure, probably understates the informal trend (“Latham effect”) in this election.
Hopefully what the ALP machine takes from Indecision 2010 is that adding 1.8% to their primary vote would have delivered a fairly comfortable victory, so you do actually have to give people a reason to vote for you.
Wow.. there is intelligent life in Wingham
I guess the question we all want answered is – does an increase in informal votes adversely affect one side or the other? Any way to come at this problem?
I wonder if the extra informal voters actually deserted Labor perhaps thinking they would still win and now cathartically may return at a soonest election.
If the fibs costings are exposed as bogus by the independent Treasury and Finance, assuming the Independents stick to their guns, surely they risk oblivion?
I hope also the Independents address the fact that millions of people are unaware that those born after 1964 will get no pension and that they won’t have nearly enough to survive on.
The mining tax is the only thing that’s going to help at the moment and it is a cruel politician that takes that away, pushing the problem further away as they did last time they blocked a rise.
It’s a cruel MSM and ABC who shine lights in the voters eyes to keep them unaware of this and other benefits.
Firefox 3.5.7 displays this site perfectly.
Perhaps it’s time for Vane to update.
In 2007 – Poss kept us going by showing how the ALP were going to win and King Rattus Nonveritas would be deposed. This time… he’s as anxious as the rest of us. On the surface it would seem that going by past record of the 3 indies, and TA’s dummy spits, it would seem that TA will not be PM, but until it’s done and dusted… noone can be sure.
Logic would dictate that Julia remain PM (having the benefit of incumbency), analysis of the voting would also favour Julia, as the swing to the Greens was nearly double that of the swing to the coalition, and with the coalition having swings against it in Vic, SA, and Tas. Julia’s response to the 3 indies in comparison to Tony’s condescending and patronising “I Love The Bush” and refusal to allow Treasury to review his policy costings also would tend to favour Julia remaining as PM.
The Greens having BoP in the Senate also favours Julia as PM.
Two of the three indies support climate change action, NBN, and resource tax.
The Green supports climate change action, NBN, and resource tax.
I think Wilkie supports those issues as well.
Australia took a jump to the left, not a step to the right.
It should be Julia that emerges as PM given all that, but it’s not a lay-down misère.
Possum
Is there a skew to say Labor electorates? like the US version of Democrat dementia?
I don’t know about (?Abbott) “lay-down” but that was certainly “misère” Dave.
I am using Opera and Firefox, in Mint Linux (based on Ubuntu) – no problems.
If the Greens in Cowper were handing out a HTV with just a 1, (no other preferences) on the obverse, does that mean that federal HTVs do not have to be registered, or just that there is no ‘standard’ that applies to them?
Of the 15 divisions with the highest informal vote, 14 were from NSW.
Of the 30 divisions with the highest informal vote, 22 were from NSW.
Maybe they are still getting over State of Origin?
http://vtr.aec.gov.au/HouseInformalByDivision-15508-NAT.htm
I notice that the seats with the highest informal votes are all Labor seats. What’s the correlation between being a Labor seat and voting informal? Is it tied in with education level, socio-economic status or the number of McDonalds in the area?
Poss – or someone else with access to all the info. Could you do an analysis of what Andrew Bolt’s latest hissy fit would mean – ie if all electorates were same size as in Tassie. My hunch is he might not like the results. The National Party certainly wouldn’t. My guess is it would increase dramatically the differential between ALP and Liberals in the cities – ie the ALP would gain more seats than would the Libs. The Nats might gain a couple, but not that many.
On the education issue, I think you can add a specific variable: the dumbing down of the electorate by the MSM.
Thank you Rupert, in particular.
@45
I think Bolt has a point here, although perhaps not what he was trying to make. I’ve long thought we should expand the House (and consequently Senate) so that mainland electorates have a similar quota to Tassie.
It would solve the problems of Tassie’s alleged advantage with guaranteed 5 seats.
It would solve the problems of ACT’s alleged disadvantage in having only two seats because they’re like 2.499 of a quota.
It would eliminate the scuffling over whether the NT were really 1.50000001 of a quota or not.
Nats would love it as it would reduce the size of country seats, and I think all sides would support it in principle by allowing more compact, focussed electorates. No more having outback north-western NSW linked with Albury. The political impact would probably be minimal since the vast majority of new seats would be in politically marginal growth regions.
Just looking over this again while showing someone the figures. With the OPV dummy, it’s entirely possible that this is picking up a spurious correlation, right? That there were some other state-specific factors which were common to NSW/QLD (e.g. MSM’s suggested dissatisfaction with the incumbent ALP governments) but not the other states?
If so, then in theory it’s possible that an awareness of the difference between state and federal systems led to an on average lower informal vote in NSW/QLD, but that other state-specific factors pushed the coefficient back above 0. I doubt this is the case, and certainly buy the assumption that the two systems are likely to create confusion (rather than lead to this hypothesised higher level of care or awareness), but it’d be interesting to see some data with other dummies or instruments to disentangle other possible state-related factors.
Ciannon,
Ordinarily it could well be spurious, except that every federal election shows the same result – where OPV states have a higher level of informals than others
Just wondering, ever tried to do an analysis of intentional informals (i.e. Senate informals) versus accidential informals (i.e. difference between Reps and Senate informals)? The latter could be used to compare data across elections, since the former takes out the variability of year-specific issues (if the election is about ‘nothing’, the senate informals seem to go up)
hmmm … meant to say “intentional informals (i.e. Senate informals) AND accidental informals”