Research by Dr Scott Davidson, De Montfort University

Although the ageing of the UK population is well documented, less well understood are the implications for a first past the post electoral system such as ours, with the importance of marginal seats in campaigning. My research suggests that Labour and the Liberal Democrats are defending 57 “grey marginals” against the apparent rise in vote share for the Conservatives since 2005.

A note on methods (more details in the full report). I have taken the age differences in turnout from 2005, and assumed these will remain. Of course, future numbers will vary, but at the moment there is no indication of a sudden uplift in the turnout rates of younger voters. The charts below show the estimated age breakdown of turnout for constituencies.

The definition of the grey vote is all voters 55+. This can be justified on several grounds; people in their 50s start to experience age discrimination in employment; they are approaching retirement and may be worried about pensions; and their own parents are likely to be in their 70s or 80s and may be requiring long-term care.

The Grey Marginals

Labour are defending 38 seats with notional majorities of 5,000 or less, but where it’s estimated that over half of turnout will be made up by the grey vote. What immediately stands out is that it is the Conservatives who are challenging in second place. (The only exceptions are the three seats in Wales.) Most of these seats were Labour gains in the landslide of 1997. A significant proportion are in the midlands and north west, and dominated by small towns or seats that are a mixture of suburban and rural wards. Perhaps the most interesting aspect is that they exist at all – a Lab-Con grey battleground is a new electoral phenomenon – if the Conservatives do win, then Labour’s recovery strategy, I suggest, will have to prioritise how it wins back older voters in seats such as these.

For the Liberal Democrats there has been a longer of history of battling with the Conservatives in grey seats. Indeed, with 19 grey marginals, this amounts to almost one third of their current parliamentary representation. Their battles with Tory challengers in these seats will have been a core concern for Lib Dem strategists. Their grey marginals are heavily concentrated in the south and south west, and they will have a special challenge in defending the two wholly new seats of York Outer and Chippenham.

Grey Power?

It is now a feature of modern campaigns for commentators to proclaim older voters as one of the pivotal battlegrounds in determining the final outcome.

Certainly, it has been the recent drops in turnout amongst younger voters which has accelerated the impact of population ageing. Younger age groups in the 1970s showed lower turnout rates, but in subsequent elections and as they grew older their turnout increased. But, this trend seems to have been broken in the 1990s, and first time voters in 2001 maintained their low participation rates in 2005.

Older people are more likely to vote, join campaigns and contact elected representatives. They have higher levels of political literacy and are more likely to follow the campaign closely in the media. It would be a foolish strategist who ignored these voters. However, the grey power model is flawed. Older people are not homogenous in political attitudes nor do they vote as a single block who perceive a single shared interest. They are concerned about the prospects for their own children and grand-children and will be divided by hugely varying personal social and economic circumstances.

That said it is likely that parties can succeed if they adopt a sophisticated segmentation of voters by life stage. Furthermore, it is clear that there are issues that particularly impact on the quality of life for older voters, and if grey voters were to perceive one party to be discernibly stronger, or weaker, on those issues, this could become significant. Any party that scores badly with older voters is going to have to do remarkably well elsewhere to have even a remote aspiration of winning a majority in the Commons.

** The data was developed with support from Age Concern, who have used some of the findings for the launch of AGE UK, the new organisation that has arisen from their merger with Help the Aged.

Dr Scott Davidson

Twitter: @framingthedot

A guest slot by Matthew Lebo, Associate Professor of Political Science, Stony Brook University

Academics make electoral forecasts that differ from those of poll-watchers. First, we use historic data and statistical methods to make our predictions, not simply the latest polls. Second, in addition to accuracy, we also want to learn something about the fundamentals that move voters and decide elections. Third, we want to know more than how people would vote if an election were held today - we investigate where the electorate is going and where it will be on election day.

For us, a good forecast is accurate - preferably over multiple elections - and provides a good amount of lead time. Early forecasts are judged against the results, rather than looking at the closeness of the last polls of the campaign. We aspire to give an early forecast with a margin of error smaller than election-week polls.

The forecasting model developed by my colleague Helmut Norpoth and me is one of several by academics making the rounds this election season. Slides and the complete paper are available here: http://ms.cc.sunysb.edu/~mlebo/ . To predict the vote, we use the history of party swings in elections since 1945 as well as the impact of the PM’s satisfaction rating. This gives us a prediction of where the electorate is headed, rather than choosing the current poll we trust most and then hoping it holds out over the final weeks of the campaign.

Using election results and public opinion data on PM approval gives an equation to predict 2010. It is summarized in the first figure. The graph itself was determined by the model the moment the 2005 results were known. However, we waited until 2 months prior to the 2010 election to determine where X goes. A given value of total vote intentions for the major parties and the value of PM approval determines the predicted vote. Nowhere in our model is the relative share of vote intentions for Labour and the Conservatives. Using January polls, the model predicted a 6.9% lead for the Tories. Brown’s rise in approval in February led to a revised 3.4% Conservative vote lead. Using a combination of polls from then and this Monday, the estimate is a 4.3% Tory lead.

Next, we feed the predicted 4.3% lead into a model that translates votes into seats. To predict the distribution of seats, we study the statistical trends in this translation since 1910. Our method allows some, but not all, of the bias in the electoral system to carry over from election to election and, from 1910 to 2005, makes closer predictions on average than relying on some “uniform swing.” Much of the bias in the electoral system from 2005 will still be present in 2010 and a 4.3% Conservative lead predicts a near dead-heat in seats.

Our vote forecast of a 4.3% Tory lead translates into a prediction of 287 seats for Labour and 285 seats for the Conservatives. A hung parliament. A coin toss for the largest party.

Of course, being just right well in advance would be an impressive feat. Uncertainty exists and we quantify it to estimate the likelihood of various outcomes. Uncertainty comes from several places: the PM approval value, the impact of PM approval on votes, the historic movement of seats, and the translation of votes into seats. Allowing for uncertainty, we simulate elections under the many ways the model could truly work and the many values our data could hold. So, we simulate 1,000,000 elections under various conditions that could exist in our model and in our data. The results of these simulations tell us about the probabilities of different outcomes.

The second figure shows the distribution of possible Conservative seats based on the February values of PM satisfaction given by MORI and the latest from YouGov. The peak of the distribution, 285, is our best estimate for Conservative seats. The range of possible outcomes is, of course, very wide. But some possibilities are more possible than others. Significantly, in only 4.47% of the simulations do the Conservatives win a majority (> 325) of seats.

The Conservative seat lead figure covers the relative party fortunes. Anything to the right of zero, 47.7% of the simulations, indicates a Conservative lead in seats. That is, even with a prediction of a 4.3% vote deficit, the model predicts a 52.3% chance that Labour will hold onto a lead in seats.

Still, the chances of a Labour majority are very small (1.33%). The range that can give a hung parliament is wide and our distribution is smack in the middle of it meaning that the probability of a hung parliament (94.2%) is near its maximum. Any change in Gordon Brown’s popularity will drop this number substantially.

What are the potential problems for our forecasts? The accuracy of the PM satisfaction values is not a principal worry - MORI and YG are in fairly close agreement and we are most interested in comparing them to previous polls by the same firms not to other firms like ICM who sample differently and the ask the question differently than all the polls since 1945 we use in the model.

More worrisome is our model’s omission of the popularity of the Opposition leader. This has not been a problem historically for our model, but if Mr Cameron proves to be uncommonly more popular than the PM (think 1997), we could be under-predicting Tory support. Also, Mr Brown’s gains of late could dissipate. Lastly, our model is based on a very small sample - 17 elections for the vote and 26 elections for seats. Economists usually make their forecasts with hundreds or thousands of data points and still have great difficulty. Will we do better than they typically do? We’re betting on it.

Research by Dr Jane Green and Dr Will Jennings, Manchester University

A new measure by researchers at the University of Manchester shows a significant problem for Gordon Brown: the mood of the country is against Labour on policy competence. It is as serious for Gordon Brown as it was for the Conservatives before Labour’s landslide victory in 1997. The current decline against Labour is precipitous.

Green and Jennings argue that it is important to study the public mood across a large number of issues: public ratings of party policy competences move together.

This graph shows the authors’ measure, “macro-competence” over six incumbent governments, annually, from 1950 to 2010 (the final data point is February 2010 – the most recently available).

The measure is constructed using a comprehensive dataset of policy questions about trust, competence, and handling, obtained from recorded opinion polls and surveys since the 1950s. Around 2,500 administrations of question were used by Green and Jennings to compile the measure. The data are analyzed extracting the common variance using an algorithm developed by Professor Jim Stimson (University of North Carolina, Chapel Hill). This provides an indication of the mood in the country about which party is most competent on policy issues.

The following graphs show macro-competence, annually, for Labour and the Conservative party.

These data point to an important advantage for the Conservatives, although the increase is not of the same order as the decrease for Labour. This may explain why the Conservative party is not doing better against an unpopular Labour government and Prime Minister. The measure is highly correlated with vote choice, leader approval, and many other indicators. For most governments a small up-tick precedes an election. It is yet to be seen whether this will be true for Labour this coming May.

Further information is available from the authors.

jane.green@manchester.ac.uk

william.jennings@manchester.ac.uk

Mike Smithson’s polling column for the News Statesman is here

UNS - Exploring the Distortions

I’ve put together a short series on UNS – what it is, what’s its track record, and what levels of distortion have occurred in recent elections. This is part three of three.

It is an article of faith that the electoral system is inherently biased against the Conservative Party. Certainly a UNS calculation from the position as of the 2005 General Election is very harsh on the prospects of the Tories. But is this built in? Even with a marginal boost unwind and tactical vote unwind, is there a residual tilt to Labour?

Let’s rephrase that. Was there a residual tilt to Labour?

In the run up to 1987, we can explore the distortion from a “level playing field” by simply invoking UNS from 1983 and plumping for a level score. We can see what lead each of the Big Two would need for a majority. To do this, I’ve held the Alliance/Lib Dem score at what they actually got, and varied the “Big Two” to keep their total share between them at what they actually got.

At level pegging, on 37.4% for Labour and Tories and the Alliance at their actual 23.1%, UNS says that this should have happened:

Con Seats	Lab Seats	Alliance Seats	Advantage
307	297	22	10 to Conservatives

This is what UNS says should have been the requirements for various points of interest:

Conservative majority	Con lead 3.2%
Labour majority	Lab lead 5.2%
Level on seats	Lab lead 0.7%

The pro-Labour distortion is definitely not apparent. Indeed, the Tories have a distinct (albeit slight) advantage. The BES surveys from this time show a slight potential tactical vote against Labour, supporting the distortion, and it’s undeniable that Michael Foot appealed more to the Labour core than the floating voter – and it’s the outcome of 1983 that created this distortion.

In 1992, we invoke UNS from 1987 and carry out the same exploration. At level pegging (Con and Lab both on 39% and the Lib Dems on 18.3%), this is what should have happened:

Con Seats	Lab Seats	Lib Dem Seats	Advantage
313	299	15	14 to Conservatives

This is what UNS says should have been the requirements for various points of interest:

Conservative majority	Con lead 2.6%
Labour majority	Lab lead 4.2%
Level on seats	Lab lead 1.0%

After 1987, the pro-Tory advantage increased – especially as the Lib Dem share dwindled. However, when push came to shove, the 14 seat advantage proved more than illusory – and the distortion not just unwound but wound up to Labour sharply – as can be seen when we look at the electoral landscape post 1992 – on the runup to 1997. Remember that the landscape used for UNS calculations for the next election is what actually was the case for the previous election.

From UNS from 1992, a dead heat in the polls should have given (with Con and Lab both on 37.9% and the Lib Dems on 17.2%:

Con Seats	Lab Seats	Lib Dem Seats	Advantage
287	324	23	37 to Labour

Remember that 14 seat advantage that the Tories should have had? Well, at the 1992 election, it actually turned into a 37 seat advantage to Labour.

Conservative majority	Con lead 6.3%
Labour majority	Lab lead 0.9%
Level on seats	Con lead 2.6%

The same lead that would have given them a majority (under UNS) one election earlier would be not quite enough to draw level on seats in a hung Parliament. However, as events turned out, that 37 seat advantage to Labour (from a 14 seat advantage to the Conservatives one election earlier) proved to be eclipsed by the magnitude of what did happen. As can be seen when we look at what UNS from 1997 to 2001 says should have happened in a dead heat (37.4% each):

Con Seats	Lab Seats	Lib Dem Seats	Advantage
252	340	37	88 to Labour

Blair outdid UNS rather handily in 1997, obviously. He’d have received a majority of 21 when level in the polls.

Conservative majority	Con lead 10.6%
Labour majority	Con lead 1.6%
Level on seats	Con lead 6.7%

This is where the distortions really became embedded. And just to add insult to injury, the distortions increased rather than decreased. Those who had lent Blair their vote tactically and those marginal voters who had decided to “give him a chance” could have been viewed as a provisional boost. That 88 seat distortion was a huge pressure on the electoral fabric – and the Labour first term did nothing to make them fear they’d made a mistake.

The 2005 landscape was fashioned in 2001. On UNS from 2001, a dead heat (at 34.7% each) would have given:

Con Seats	Lab Seats	Lib Dem Seats	Advantage
207	351	59	144 to Labour

A dead heat should have given a Labour majority of 56. A 144 seat distortion advantage. Howard had no chance of winning a majority, realistically.

Conservative majority	Con lead 12.6%
Labour majority	Con lead 2.8%
Level on seats	Con lead 7.9%

And now? According to UNS, with the landscape that emerged from the 2005 election, a dead heat (assuming the Lib Dems on 20% and the Conservatives and Labour at 35% each):

Con Seats	Lab Seats	Lib Dem Seats	Advantage
241	330	49	89 to Labour

Pretty much pegged back to the distortion that came out of the 1997 election. The milestone requirements bear that out:

Conservative majority	Con lead 10.2%
Labour majority	Con lead 0.4%
Level on seats	Con lead 6.8%

So in one handy table, let’s put up the changes in distortion from UNS. What was the seat advantage coming in to each election, and what did UNS say were the thresholds needed? And how did they change?

	Seat advantage	Con majority	Lab majority	Level on seats
1987	Con 10	Con lead 3.2%	Lab lead 5.2%	Lab lead 0.7%
1992	Con 14	Con lead 2.6%	Lab lead 4.2%	Lab lead 1.0%
1997	Lab 37	Con lead 6.3%	Lab lead 0.9%	Con lead 2.6%
2001	Lab 88	Con lead 10.6%	Con lead 1.6%	Con lead 6.7%
2005	Lab 144	Con lead 12.6%	Con lead 2.8%	Con lead 7.9%
2010	Lab 89	Con lead 10.2%	Con lead 0.4%	Con lead 6.8%

Take a look at that variation. Bear it in mind when you use a UNS calculator. Read across from each election – that is what UNS said should be the case going in. The line below (the landscape seen in hindsight after the actual election was fought becomes that forecast for the next election) is what it actually was.