General Election Forecast based on Uniform Swing by Region

On May 15, YouGov produced a General Election opinion poll broken down by the eleven Regions of Great Britain. It seems impressive with 14395 GB Adults, plus 1040 London Adults, 1017 Scottish Adults and 1018 Welsh Adults. However, with fieldwork on 24 April to 05 May, it might be a little out of date. By combining this with the General Election Results by Constituency (available for the British Election Study) I have been able to produce a crude forecast for the General Election on June 8th.

The starting point in the General Election Results of May 2015, shown in Figure 1. Since then Con has gained 1 seat from Lab (Copeland), and lost a seat to LD (Richmond). The sole UKIP MP, Douglas Carswell, left the Party in March to become an Independent. These are ignored.

Note that the 18 Northern Ireland constituencies are not included. The 331 Con seats are against 326 for a majority in the House of Commons.

I made the following assumptions.

  1. Within each constituency, for each Party I have assumed the change in the vote is the difference between the regional share of the vote in 2015 and the opinion poll share from YouGov.
  2. If the constituency vote share in 2015 was less than the regional drop in vote share between 2015 and current opinion poll, then the vote is nil.
  3. A party may have a predicted vote despite not having a candidate. There are two instances where this is possible. First is that UKIP are not standing candidates in every constituency. Second is that the Progressive Alliance of Lib Dems, Greens, Labour and the SNP are standing down candidates to maximize the impact of the anti-Tory vote. Guido Fawkes’ summary of 16th May is here.

This simple model produces the forecast in Figure 2.

Implied Conservative majority is 128, up from 12 in the previous Parliament. The Lib-Dems also increase there number of seats, whilst SNP lose 9. UKIP’s “gain” is in Buckingham, the seat of the Speaker. This is due to a flaw in the crude model.

The Party gains by region are in Figure 3

Of note is that Labour do not gain a single seat, as YouGov estimate that their popularity has dropped in all but two regions. In the South East and the South West Labours’ presence is quite low. The SNP in Scotland lose seats to both the Conservatives and the Lib-Dems, but the loss of 9 seats is would still mean they have 47 of 59 seats.

These switches in seats are shown in detail in Figure 4.

My very crude forecast can be compared to the current forecast by Martin Baxtor at Electoral Calculus of Con 409, Lab 167, LD 7 & SNP 46. The Conservative majority is 168, 40 more than my own.

Another comparison is the mid-point of the spread betting at Sporting Index. This Con 399, Lab 159, LD 15.5, SNP 45.5. The implied Conservative majority is 148, bang in the middle of my own and Martin Baxters’.

In subsequent posts I intend to

  • Clear up the obvious errors.
  • Refining the forecast for Scotland based on the local election data of May 5th.
  • Look at the forecast for Wales, where I believe YouGov might be out of line with popular opinion.
  • Update in relation to more recent, but National, polling. For instance the recent strengthening of the Labour poll share and the fall in the UKIP share.

Kevin Marshall

 

Did the Conservatives field too few candidates in the Scottish Council Elections?

A couple of weeks ago posted Will Ruth Davidson be Apologizing to Voters After the Scottish Local Elections on May 4th? My contention was that the Conservatives has underestimated the strength of their growing support, so had fielded too few candidates. Under the Single Transferable Vote System, if a Party fields too many candidates in a ward then they will compete against each other. So I believed that the Conservatives, unsure of where their vote might lie, played safe. This was on the basis of my forecasting, before the General Election announcement the Conservatives gaining 150 extra seats, and achieving 21% of the First Preference vote. I was then seeing signs further improvement in the opinion polls, but with no extra candidates to achieve extra seats. In the event, the Conservatives gained 161 more council seats than in 2012, with 25.3% of the FPVs. Part of the reason for this was the other major parties. The Labour Party did much better than I expected and the SNP did worse. But there is still evidence that the Conservatives fielded too few candidates.

Figure 1 shows the seven Scottish Councils where all the Conservative Candidates won seats. Given that (a) of the 337 wards with Conservative candidates 296 had only one candidate, and (b) that support for any Party tends to vary across wards, the fact that every candidate one suggests too few candidates. Aberdeenshire and Moray stand out most clearly in this respect, as the total FPV vote was well in excess of the percentage of seats won. But South Ayrshire Council was possibly the most significant, as with three more seats and the Conservatives would have had a majority on the 28 seat council. In five of these councils they were also the largest party.

It should be noted that the Conservatives were not the only Party which achieved the feat of 100% of candidates being elected. The Liberal-Democrats saw elected all 6 of their candidates in East Dunbartonshire. Here the Conservatives saw 6 of their 7 candidates elected. The only other example of a party achieving a 100% success rate for a council was the SNP in the Shetland Islands. Their sole council candidate, Robbie McGregor, won the Shetland South seat uncontested.

This theme of insufficient candidates is also suggested in the councils where more than 75% of candidates were elected.

There are three councils where the FPV share exceeded the percentage of seats won. Councils like Aberdeen City and Stirling are where the Conservative vote share varies considerably across the wards.

A particular ward that stands out where the Conservatives had too few candidates is Carse Gowrie, Ward 1 of Perth & Kinross Council Area.

After vote allocation, Angus Forbes won more votes than the two SNP candidates combined. The Courier local newspaper did a series of short articles on all the wards in this council and others in the area. For Carse Gowrie they wrote:-

 Former scout leader Mr Forbes said: “I knew we would do well, because the Conservatives always have in Carse of Gowrie.

“I was surprised to increase the vote, though.”

He said: “Sadly, what I was finding was that people were voting on national issues, rather than local ones.

“It was all about independence. When I was out canvassing, what I was hearing was: We’ve got to get rid of the SNP, we’re fed up hearing about independence.”

This comment could be highly significant in that First Minister Nicola Sturgeon is trying have another Scottish Independence Referendum just four years after the previous one, despite the 2014 one supposedly being the last one for a generation. This would also explain why the Labour Party achieved 20.2% of the FPV vote, a share significantly above the Labour share of recent Scottish opinion polls. This being a a reversal of the 2012 and 2007 council elections, where the FPV share was significantly behind the FPV share. Mrs Sturgeon’s move could being viewed by a very cynical attempt to win independence on the basis of unfounded scary stories about Brexit, before they are contradicted by the real world evidence after March 2019.

What the results indicate for the General Election

Whilst the Conservatives might have been able to gain a few extra council seats if they could have better predicted the surge in support, the important issue is the indications for the General Election. If it is the case that the General Election swing might be even larger for the Conservatives in the council areas where they did well, and an maybe an improvement for Labour in their traditional Scottish Heartlands. At the Electoral Calculus website, the current Scotland GE forecasts are

CON 12 (+11), LAB 0 (-1), LIB 2 (+1), UKIP 0 (+0), Green 0 (+0), SNP 45 (-11)

For the Conservatives, the council election results are consistent, but for Labour they may win an extra seat, rather than lose their only Scottish seat in Edinburgh South.

Kevin Marshall

Results of the Scottish Council Elections

The Council Elections were held last Thursday 4th May, and the results in terms of seats were announced on Friday. It was only today that the Elections Scotland have published the summary details, including the First Preference votes. I have complied three brief summaries. The 2012 data used for comparisons is from the Lincoln Report on Report on Scottish Council Elections 2012.

Figure 1 shows the SNP were way ahead in terms of total seats won, the Conservatives second and Labour in third. In terms of change from 2012, it is the Conservatives that performed best, increasing the number of seats by 161. Labour lost a third of their seats, and the Independents were collectively down by a sixth on the seats won in 2012.

Figure 2 shows the SNP getting again ahead in terms of First Preference Votes, and on the same share as five years ago. The Conservatives are second on 25.3% and Labour third on 20.2%. For comparison, the latest YouGov opinion poll for Scotland of Westminster voting intentions, (of 24-27 April) gave SNP 41, Conservative 28 & Labour 18. People often vote differently in local elections to General Elections, and in Scotland, Independents are quite strong. But the difference is striking, and may indicate where the vote is moving. Compared to the last opinion poll, SNP -9, Conservative -3 and Labour +2. On that basis the Local Elections were bad news for the SNP. The Labour Party appear to have bottomed out, and the Conservatives are doing extremely well.

Figure 3 is the most interesting in terms of indications of voting intentions going into the General Election. I have shown the percentage of first preference votes by Party in each of the 34 councils.

I have highlighted the Party that gained the highest shared of First Preference Votes in each Council. They are SNP 16, Con 10, Ind 5, Lab 1.

A quick comparison with the Electoral Calculus General Election seat predictions. The Westminster constituencies are not necessarily the same as the councils.

Labour was only ahead in East Lothian. Electoral Calculus only gives Labour a 14% chance of winning, as against 45% for the SNP and 40% for Conservatives.

At a quick glance the Conservatives are ahead in all their target constituencies.

In the Scottish Borders, the number one target they achieved nearly double the FPV of the SNP. Although there is a strong vote for Independents, the 76% chance of Conservatives winning seems more than justified.

The better news for the Conservatives is in the long shots. Stirling has a 43% chance of winning, against 49% for the SNP, yet were 2.4% ahead in the FPVs. Angus has a 36% chance of winning, against 63% for the SNP, yet were 1.7% ahead in the FPVs. Ayr Carrick and Cumnock has a 32% chance of winning, against 59% for the SNP, yet were 13.2% ahead in the FPVs.

Kevin Marshall

John Curtice on Scottish Local Elections

I have made some quite bold statements about the Scottish Local Elections. It might be worth comparing these with the comments made by Britain’s leading psephologist, Prof John Curtice who is behind the What Scotland Thinks website and was the BBCs leading expert on the 2015 General Election and on EU Referendum. Comments quote in a BBC article on 30th April.

Meanwhile, analysis by politics professor John Curtice has suggested that the SNP and the Conservatives are likely to make gains in the local council elections.

I agree, forecasting about 100 seat gains for the SNP, and 150 seats for the Conservatives.

He said Labour looks set to fall back heavily.

I agree, forecasting about 250 seat loses for Labour.

The Single Transferable Vote (STV) multi-member ward system means that parties try to avoid standing more candidates than they think can win as they can affect each other’s chances of securing a seat.

Labour is standing 44 fewer candidates in this election than it did in 2012.

Prof Curtice said: “The changes in the number of candidates being nominated by the parties give us a strong clue as to how they see their chances.

The Greens above all are evidently hoping to make a significant breakthrough, while the Tories and the SNP would seem to anticipate doing better than they did five years ago.

Labour, in contrast, would appear to be expecting a setback.

As a result of the sharp reduction in the number of candidates it is fielding, the party can only retain control of Glasgow, West Dunbartonshire and Renfrewshire if every single one of the party’s candidates there secures election.

And that will only happen if the party actually manages to outperform expectations.

I agree on the points, but Prof Curtice being somewhat circumspect and polite to all sides. The Greens are not looking to make a major breakthrough, they are just fielding more candidates. The Tories have underplayed their hand, having a few extra candidates, but are not fully reflecting their recent surge in the opinion polls. If they had done, they would have fielded two or more candidates in more than 41 wards they have done.  But even with the surge evident early in the year. they probably thought better to play safe, than guess where the vote surge would be concentrated and come unstuck. At least then Ruth Davidson can now give an apology for underestimating support, and use that as a springboard for greater success at the General Election.

However, it is the Labour Party that have failed to game the system the most. They have pared back the number of candidates, making it certain that they will lose most of the majorities on the councils which they currently hold. But 44 less candidates is still far too many to maximize the seats won considering that their share of first preference votes is likely to be around half what it was in 2012. Figure 1 shows that in 145 wards Labour have more than one candidate. Most of these candidates will end up competing against each other, maybe resulting in no Labour councillors in many wards where they are traditionally strongest, where one candidate could have got elected. There is a very good reason for this strategy, figure 3 (from this post) shows why.

The candidates generally match the number of current Councillors. However, I make it seven councils that Labour can retain control of if every candidate is elected, not three. The official candidate list from Elections Scotland is here.

Prof John Curtice makes the more general comments, whilst I make specific predictions. I can be more easily wrong, but in making the basis of the forecasts known, then comparing my forecasts to actual outturn can give a greater understanding of the changes from 2012 than more coded comments. But then my more partial statements would never be allowed on the BBC.

Kevin Marshall

 

Revised Scottish Local Elections 2017 Forecast

A previous forecast for the Scottish Local Elections was made before the General Election announcement on April 18th. Upon reviewing the forecast, I found that I had not allowed in the forecast of changes in numbers of council seats, for the impact of different average population per council seat. Allowing for this factor roughly offsets the movement in opinion since that announcement. In particular the fact that a Labour Councillor represents on average a large population than a councillor from other parties offsets the impact of a small increase in support for Labour since the General Election announcement. I see no reason to revise significantly my previous forecast of Labour to lose 250 seats, with the Conservatives to gain 150 and the SNP 100.

After the General Election was announced at least two Scottish opinion polls of Westminster voting intentions have been produced – one by Panelbase for The Sunday Times, the other by Survation for the Sunday Post. Both polls show the SNP down and both the Conservatives and Labour up slightly. One problem with using this opinion data is that people might vote differently in the local elections. For instance, in Scotland as a whole, Independent candidates in 2012 received 12% of the First-Preference votes and won 16% of the seats. I would expect that that the SNP would lose out the most to Independents, followed by maybe the Conservatives and the Liberal Democrats. This hypothesis can be validated against the data. The University of Strathclyde’s “WhatScotlandThinks.org” has the opinion poll data going back to 2007. For 2007 and 2012 I compare to percentage shares of seats votes with the opinion polls nearest to the local elections in Figure 1.

There is a result that I did expect. That is the Conservatives did comparatively worse in terms of seat percentage to opinion poll percentage. This was worse in 2012 than in 2007, as their share of First Preference votes fell in many wards below the threshold required to win seats. What I did not expect was that the SNP’s seat share was about the same as the opinion poll percentage in 2007 and slightly above that level in 2012, despite Independents winning 16% of the seats. Most unexpected is the Labour Party, which has the biggest deficit between opinion polls and seat share. There are three vague factors, that might be valid. That is different voting behaviour in local elections and general elections; lower voter turnout in Labour-voting wards and inaccuracies in the opinion polls. In the first it could be that some people were voting SNP in the local elections and voting Labour in General Elections. But this does not gel with what happened in the 2011 Scottish Assembly elections and the 2015 General Election. There is another factor. Local Councils represent different populations, which only partly reflected in the size of the council chamber. The most populous is Glasgow, with an estimated mid-2015 population of 606,300 and 79 Council seats.  The least populous is Orkney Islands, with an estimated mid-2015 population of 21,500 and 21 Council seats. So a Councillor in Glasgow will represent nearly nine times the number of people as in Orkney. There are good reasons for this differential. If the Councillors per head of population were made roughly equal (4390), then Glasgow council chamber would increase to 138, and Orkney would reduce to 5. But this does impact overall. Using the 2012 seats and within each council, dividing the population by the seats, gives figure 2.

About half of  the difference between the Labour Party’s differential between First-Preference vote share and seat share can be explained by the fact that their support is concentrated in the larger council areas where the average seat population is larger. The SNP were also impacted by larger than average seat population , but not by nearly as much.

This does not matter for seats won on councils, but it does impact on the net change in council seats. In particular, like others, I believe that the SNP will make large gains from Labour in the cities and larger towns, with Glasgow being the key area. But I also believe that the SNP will lose council seats to the Conservatives and the Independents. For this reason, I estimate that the average SNP seat population will increase by about 5%. With it they should gain control of 5 to 10 councils. However, if the drop in General Election support is from around 47% to 41% the net seat gain could be around 50, instead of the 100 previously predicted.

Labour are hit with three combined impacts of the likely fall in the first prefence votes. First is the failure to reach the threshold first preference votes to win seats. Second is that this threshold will be a higher percentage of the vote than for the Conservatives or the Liberal Democrats, as Labour have fielded more than one candidate in nearly 150 wards.  With such a low share of the vote, under the STV system Labour Party candidates will be competing against each other for votes. Third is that Labour have larger than average population per seat, so the percentage of the seats won will be lower than the opinion polls suggest. For these three reasons combined, even if the General Election show a slight recovery from 15% to 18% of the popular vote, their share of the Scottish council seats won, could be still be less than 13% of the total, the point where total number of seat losses exceeds 250.

Kevin Marshall

Will Ruth Davidson be Apologizing to Voters After the Scottish Local Elections on May 4th?

The Conservatives in Scotland are likely to show large gains in the Scottish local elections next Thursday.  So why should Ruth Davidson end up have to make an apology?

Consider the reasons that are likely to be large gains next week.

First, is that in 2012 the Conservatives did rather badly. They lost 28 seats to 115 seats, less than 10% of the total. In first preference vote share they went down over 2% to 13.3%.

Second is that since the 2015 General Election, when they received 14.9% of the vote – worse than the 2012 local elections with no Independents – the opinion polls have shown a consistent rise in support. By May 2016, the Conservatives achieved 22% of the vote at the constituency level in the Scottish Assembly Elections. By early this year opinion polls are indicating around 25% support.

Third is that support has, if anything, risen further in the last couple of months. Polls conducted since the General election was announced show GE support at 28% (Survation/Sunday Post) and 33% (Panelbase/Sunday Times). Below is a summary from Martin Baxter’s Electoral Calculus Website

On that basis local election vote could be above the 21% of First Preference Votes I used to predict gains of 150 seats. The potential embarrassment lies in the Single Transferable Vote (STV) system. Under STV – a basic alternative to proportional representation – very large council wards have three or four Councillors. If a Party wishes to maximize its seats, it must optimize the number of candidates. In a previous post, I looked at the the candidates per ward.

In only 41 wards do the Conservatives have more than one candidate. In optimizing the number of candidates they have assumed that in only a very limited number of wards will they receive more than a third of first preference votes. Much below that and two candidates would end up competing against each other for votes. This is the strategy of a party, with uneven support, who still expects to get less than 20% of the vote. The problem is that is so long since the Conservatives had this level of support they do not know where that support lies. So, retrospectively, the Conservatives will realize that in many wards they could have fielded an extra candidate. This could mean that they fail to become the largest party on a number of councils, due to the prudent approach. Given that the SNP is the strongest party with the most candidates, it is they who will gain from this prudence. Hence the reason that Ruth Davidson could end up apologizing.

If this happens, and the Labour party loses out from fielding too many candidates (through matching the number of seats held in most areas), it could lead to a campaign to abandon the STV system. The SNP will likely stoutly defend a system that seems progressive and benefits them.

Kevin Marshall