Unlike the 2015 general election when the polls were essentially static (& wrong) throughout the election, the 2017 general election has seen some of the most extraordinary volatility in the polls that I can remember. If you are a Conservative supporter, the narrowing lead over Labour must be leading to anxiety and changed underwear. If you are a Labour supporter, you are probably starting to dream “can we? will we?!” It doesn’t help that your state of mind will depend on which poll you are reading and your memories of the pollsters’ failure in 2015 so how can you make sense of what is going on. I will show you how in 5 steps and to heighten the drama, I will leave the punchline to the end!
For the last 6 weeks, I have been making forecasts of the number of seats that each party will get in the 2017 General Election. If you have been following my forecasts, you will know that I have developed a variety of prediction models which all predict something different. With 10 days to go, I decided it was high time to settle on a single Final Model which is described in this post.
This post was first published on 29th April 2017 and predicted a narrow Conservative Hold. I updated this post on 21st May 2017 to take into account latest data.
Welcome to the first of my constituency forecasts for the 2017 General Election. I’ve chosen to start with the seat of Bath currently held by the Conservatives for two reasons. First, it is where I live so I have a personal interest! Second, it is the bell-weather seat for the Liberal Democrats when it comes to the success of the anti-Brexit strategy. Fail to take Bath and they can kiss goodbye to any chance of making the election a success.
MY FORECAST – Lib Dem GAIN but still very marginal
The results are in and it is now time to review my predictions of the Copeland and Stoke-on-Trent Central by-elections. How well did my by-election model do and what lessons can be learnt? Let’s look at the numbers first.
NOTE 19/2/16: This post is not yet complete. I will do my best to complete it soon as possible. Since I started writing this post, additional data has been made available and I now think that 400 out of 650 seats voted Leave. You can see an outline of my older model in my YouTube clip published in November 2016.
For those used to staying up for election night, the BBC coverage of the EU Referendum on 23rd June 2016 must have been disconcerting. Where were the figures showing how many seats Leave & Remain had won? Unlike a general election where the winner is the party with the largest number of seats, the referendum was decided by a popular vote with Leave winning with 17,410,742 votes to Remain’s 16,141,241 votes.
Also different was that the results were declared for the 399 counting areas (CA) used in EU elections rather than the more familiar 650 parliamentary constituencies. Of the 399 CAs, Leave won a majority in 270 CAs as shown in figure 1. However, the counting areas vary enormously in size from 1,799 eligible voters for the Isles of Scilly to 707,293 eligible voters for the city of Birmingham which makes it difficult to compare CAs. The apparently overwhelming victory for Leave in terms of CAs could be a statistical mirage with Leave winning small CAs and Remain winning large CAs.
Since the UK voted to leave the EU on 23rd June 2016, there have been 3 contested parliamentary by-elections (Witney, Richmond Park, Sleaford & North Hykeham) and one uncontested by-election (Batley & Spen which was the late Jo Cox’s seat). Many commentators have analysed these results to see how the referendum result has impacted on parliamentary voting intentions. Whatever voter dynamics are revealed, it is reasonable to assume that they are likely to influence future by-elections. In late October 2016 just after the Witney result, I realised it could be possible to build a by-election model by combining two sources of data.
- My own estimates of the Leave & Remain votes in each of the 650 parliamentary constituencies where I calculated that 400 out of 650 seats voted Leave.
- My interpretation of the Lord Ashcroft “exit poll” carried out on 21st to 23rd June 2016 and published immediately after the results were announced.
At the time, I described my by-election modelling approach in a youtube clip and that is worth listening to. I have made some changes to my model since then so this post is the most up to date version of my model. I will illustrate the basic principle using the Witney by-election (David Cameron’s former seat) of 20th October 2016 where the top line numbers are:
The 2015 General Election surprised many people when the Conservatives unexpectedly won a small majority though I should blow my own trumpet and say it wasn’t quite a surprise for me! One thing that wasn’t a surprise were complaints about the perceived unfairness of the First Past The Post election system with UKIP joining the Lib Dems with their criticisms.
Using the election results, I decided to see how the results would differ if a different election system had been used. The system I decided to explore was the d’Hondt system which is one of the most common PR systems in use and is used by the UK in EU elections.
The results of my analysis was published in the Significance magazine and you can see what I wrote in my article “A very different result“.
There are of course other election systems and I plan to write other posts looking at what the results might have been using those.
I am delighted to announce my 4-part series describing my analysis of the EU referendum results is now complete and available on Youtube. The full list of the clips are:
I have analysed the results of the EU referendum in some depth and I hope you find my insights informative. Some specific highlights are:
In two days time, the results of the 2015 General Election will be in. Will there be another coalition? Will Labour get in? What about the SNP in Scotland? You can now see my forecast of the 2015 General Election presented as a YouTube clip and discover many interesting facts about elections in Britain.
The bottom line is that the polls will be wrong and the pundits will be caught by surprise!