In a week’s time, Americans will go to the polls for what is known as the mid-term elections. Inevitably, the results will lead to much speculation on what it means for Donald Trump’s chances of re-election in 2020. However, I will be surprised if many commentators will look to history as a guide to 2020 and so I will fill in this gap with the help of fun 10 question quiz about US presidents.
As I write this, a plethora of economic forecasts are making the rounds in the news in the UK. In all cases, the forecasters have failed to publish their track record and these days, I will not pay attention to what they say unless their forecasts are accompanied by a track record. But, how does one go about presenting a forecasting track record to prove that one has forecasting skill? To demonstrate, I will analyse how well opinion polls have predicted General Elections in the UK and measure their track record. I must confess I was surprised at what I found out and I would urge all opinion pollsters to take note of my results.
With only 3 or 4 games to go for the teams of the Premier League, most of the season’s excitement has dissipated. Man City have wrapped up the title, the top 7 who will be playing in Europe next season is more or less settled and the former 10-team dogfight for relegation has resolved itself with a 4 point gap between the bottom 3 and the rest. Probably, the only remaining uncertainties are who will take 4th place (Spurs or Chelsea) and will Southampton escape relegation at the expense of Swansea?
The last 3 general elections have seen some significant polling errors. In 2010, the Lib Dems were significantly overestimated, in 2015 the Conservatives were underestimated and last year saw the largest ever underestimate in the Labour vote. Whilst these errors suggest that the polling industry is struggling with general elections these days, a natural question to ask is “are all pollsters equally bad or are some better than others?”
We now know the answer to who will win the 2018 6 Nations Championship. Ireland won the title with a match to spare after England failure against France resulted in my second forecasting error of the championship. There is still much to play for though in the last week with the main question being whether England do to Ireland what Ireland did to England last year and stop them from winning a Grand Slam. Whilst I am cheering on England, it is St. Patricks Day and I do have some Irish blood in me so part of me does wish Ireland well.
With 10 games to go, the 2018 EPL is now entering its final quarter and supporters of all teams are starting to wonder where their team will finish in the league. As a Newcastle United supporter, my team is stuck right in the middle of one of the tightest relegation battles in living memory. At the other end of the table, my wife’s team Spurs are almost certainly out of the running for the title but Champions League qualification is definitely in their sights. To set expectations, I have used a statistical method known as Poisson modelling to predict the final league table come May 13th and I will update this post after every round of games between now and then so please bookmark this page.
Ahead of the 2017 general election, I predicted that the opinion polls would be wrong again and that the Conservatives lead over Labour would be underestimated by 2.6%. I based this on data provided by Mark Pack who has systematically recorded every opinion poll published since 1945. In the event, I was right that the polls would be wrong but instead of an error favouring the Conservatives, the polls recorded the largest ever underestimate of the Labour vote. As a result, election forecasters were blindsided yet again and the result was a hung parliament which few saw coming.
My official prediction using my Final Election Model is that the Conservatives will make a net gain of 45 seats resulting in a working majority of 105 seats.
My forecast uses data from my latest UK Opinion Poll Tracker and it is worth reading that post in conjunction with this post. At the bottom of this post is a spreadsheet containing my prediction for each seat. I am basing all figures in this forecast on the assumption that Conservatives will have a 9.5% lead over Labour on June 8th. I arrive at that figure by taking the current CON-LAB lead of 7% in the latest polls and adding an expected 2.5% underestimate in the Conservative lead over Labour based on my analysis of historical polling errors. A knock-on effect of this assumption is that I expect turnout to be 2pts higher at 68%.
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.