An independent statistician using data to understand our world and to predict the future
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.
[Read more…] about By-Elections #2 – Review of Copeland & Stoke Central predictions
My wife is American and so it should be easy to guess what we were talking about on the morning of 9th November 2016. Donald Trump’s victory in the US Presidential election was a surprise to many people and prompted much discussion on the similarities between Trump voters and the Leave voters in June. However, my wife remarked that people may be looking at this the wrong way round and perhaps the correct question to ask is whether there is greater similarity between Clinton & Remain voters.
Identifying similarities and differences between groups of people is a cornerstone of the field of market research known as customer segmentation. It is one of my favourite areas of statistics and can be used regardless of whether the data comes from a survey or from customer records. When my wife posed her question I immediately thought of 2 ways I could answer this using segmentation methods.
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.
[Read more…] about EU Referendum 2016 #2 – Did your constituency vote Remain or Leave?
Originally posted on 19th February 2017. I then added an updated forecast on 22nd February which can be seen at the bottom of this post.
If UKIP want to supplant Labour in the North England, they must win Stoke-on-Trent Central to kickstart this trend and the odds are 2 to 1 that they will win. That is my forecast after running my by-election model on Stoke-on-Trent Central. For more details about the methodology, please read my description of how I forecast by-elections in the Brexit era.
My model uses both the breakdown of the 2015 General Election results when Labour held the seat with a 16% majority on a 50% turnout (the 2nd lowest turnout in the whole of the UK in 2015) and the 2016 EU referendum result where I estimate that Leave won with 71% of the vote on a 60% turnout. This makes this seat the 17th most Leave seat in the UK and it is worth noting that its two neighbours were #22 (Stoke South) & #3 (Stoke North). In % terms, the increase in number of voters in 2016 was the 22nd highest in the UK and has created a substantial Non-GE segment of 17% of 2016 voters that have the potential to influence the by-election. Whether these non-voters from 2015 will vote in the by-election is one of the big uncertainties and it will be fascinating to see if they do.
[Read more…] about By-Election Forecast #2 – Stoke-on-Trent Central, Staffordshire
Originally published on 19th February. Please scroll to the bottom for an updated forecast as of 22nd February.
The Conservatives are well set to take Copeland from Labour. That is my forecast after running my by-election model on Copeland. According to Matt Singh of NCP Politics, the last comparable by-election would be in 1878! For more details about my methodology, please read how I forecast by-elections in the Brexit era.
As always, we need to start with a breakdown of the 2015 General Election results when Labour held the seat with a 6% majority and the 2016 EU referendum result where I estimate that Leave won with 61% of the vote.
[Read more…] about By-Election Forecast #1 – Copeland, Cumbria
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.
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:
[Read more…] about By-Elections #1 – How to predict outcomes in the Brexit era
So the 6 Nations is underway again and the traditional rivalries are reheated. Who will win is once again on all the sports pages and there are no shortages of pundits willing to give their opinions. If you want a different way to predict what will happen, why not use the World Rugby Rankings?
Ranking tables play a big part in a number of sports but they are not widely understood among sports fans. At bottom though, rankings are intended to be used as a predictive tool for what will happen in a match. A good ranking system will be more accurate in predicting outcomes than a bad ranking system. However, a perfect ranking system is something we don’t want otherwise sport becomes boring as we will always know the outcome in advance. So as a forecasting tool, a ranking system is a curious beast. We want it to be good but not great.
[Read more…] about 6 Nations #3 – Who will win in 2017? – week 3
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 F
irst 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:
Part 1 – Where and How did Leave win?
Part 3 – What does the leave vote mean for the next general election?
Part 4 – How will Brexit play out in the Richmond & Sleaford by-elections
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!
