ManicBeancounter’s General Election Forecast 2017

Update 11/06/17

This forecast turned out to be widely incorrect. In a follow-up post I try to explore why it was incorrect. The major mistake I believe was to bend my forecast to a consensus of opinion. My follow-up post explores this further.

In the past few weeks there have been dramatic swings in the opinion polls. As a result of which I felt unable to update my forecasts. Although the Conservatives have fallen in the polls, and Labour have risen, it is a very inconsistent picture. One Yougov poll had Labour only one point behind the Conservatives. Yet Atul Hatwal at Labour Uncut believes from the canvassing returns, the Labour Party is in for a nuclear winter outside of London.

However, I will go Mike Smithson, the punters and most of the polls in predicting in showing a Conservative lead approaching double figures. Up from about 6% at the last General election, it is quite a small change considering the dramatic changes in the political landscape of the last couple of years. To use uniform swings based on the General Election 2015 would be absurd. My method has been

  • Start with the absurd. I use uniform swings – but by region – updating the post of 22nd May, with the forecast for a Tory majority of 28.
  • Kept the assumption of a Conservative revival at the expense of the SNP in Scotland, but with Labour now only slightly down on 2015. Assume that Labour are doing very well in London.
  • Assumed that in Labour constituencies where UKIP were strong in 2015, half the UKIP vote would go Conservative, and some of the Labour voters would stay at home. That is across the North of England and in Wales I am assuming a drop in turnout, which will be at the expense of Labour.
  • I have not made a general allowance for a drop in turnout. This could be significant given the appalling campaigns, and the weather forecast.

In Figure 1 is the General Election Result 2015

Figure 2 is my best guess, by region, of the result of tomorrow’s election.

This would give the Conservatives a majority of 76. This is much smaller than the forecasts in April, but much larger than that of even a week ago.

Figure 3 is the summary of seat gains

The Conservatives gain seats in Scotland, the North, Wales and the West Midlands. Labour still manages over 200 seats. Whilst this is down on 2015, it is better than Micheal Foot did in 1983, and the share of the popular vote is still around 35%, which could be higher than the share Tony Blair achieved when he won the General Election in 2005.

The part of the forecast where I will be closest is the seats with no change.

A quick look at other forecasts. Lord Ashcrofts’ constituency estimate is for majorities between 48 and 78. These are probabilistic estimates, so will not identify actual seats.

The Telegraph have published Chris Hanretty’s estimate of a 100 seat majority. Hanretty did some excellent work on the EU referendum, which I have utilized in a number of posts.

Who knows what tomorrow will bring. But having crude figures by constituency I can compare forecast with actual.

Update 8th June 18.30

Lord Ashcroft’s final estimates were published at 15.45 at Conservative Home. His central “combined probabilistic estimate” of 363 Conservative seats, giving a majority of 76, is exactly the same as mine. We differ on the other parties, as I am assuming Labour will do worse in their Northern heartlands, where disillusioned voters in the Brexit areas will stay at home. The Lib-Dems and Plaid Cymru I assume will do better due to strong local support.




Kevin Marshall


  1. gallopingcamel

     /  08/06/2017

    Greetings, mighty beancounter. I left the UK in 1982 and no longer have any understanding of the political landscape.

    Although prediction is a mug’s game I really hope you are right about Teresa May getting a mandate to exit the EU as quickly as possible. I assume that is why she called this election, or is something else is going on?

    • manicbeancounter

       /  08/06/2017

      Greetings Galloping Camel
      Prediction is useful is based on assumptions. You can then compare the results with the forecast, to develop an understanding of why the result occurred. One element is a huge amount of dissatisfaction with politics in general.
      You are right about Theresa May’s motive for calling a snap election. With a majority of 12, there could have been problems. But then the Conservatives made a complete hash of the manifesto, and let the agenda be governed by Labour. They are in denial of Brexit because many of the Labour heartlands in the North were pro-Leave, whilst most Labour MPs and the core membership were Pro-Remain.
      I am with you on wanting to get out of the EU quickly. I would prefer as few strings as possible to a deal, for both Britains and EUs sake.

      • gallopingcamel

         /  10/06/2017

        My sister who lives in Chelsea is devastated as am I. How could Teresa May let this happen?.

        Corbyn seems to have a lock on the leadership of the Labour party. He could even become Prime Minister!!!!!! I can’t imagine what will become of our once great nation with a Marxist appeaser who hates America in charge.

        • manicbeancounter

           /  11/06/2017

          To question about how Theresa May could have let this happen goes in the right direction. I do not think that it is quite the right question, as no one in fully in control of events, especially in a free and open election. But she did make some fundamental mistakes, and did not challenge the opposition sufficiently.

          I have not fully read the Conservative Manifesto, but the it seems to be a list that panders to the Labour voters, but alienates the Conservative ones. As you are aware, on the climate issue, the Climate Change Act 2008 has pushed up energy prices and distorted the energy markets. To then turn round and blame the energy companies is somewhat hypocritical. I demonstrated in 2013 when Ed Miliband announced this as Labour policy in 2013 that the (a) the wholesale energy prices were not rising (b) that the retail companies were not making larger profits and (c) the third element of rising fixed costs was explained by a combination of renewables subsidies and increased grid costs.
          Whay Theresa May – or her advisors – have done is thought that policy might be popular with the voters, so stuck it in. But this incompatible with Conservative Party ideas of competition and free enterprise.
          In general, the manifesto seems to pander to non-Consrvatives, but denies the vision of Conservatism that many hold onto.

  2. Paul Osborn

     /  10/06/2017

    Well that was impressive … maybe you need to try a different career Kevin?

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