Electoral Calculus made the most accurate pre-poll prediction of the result of the December 2019 General Election. Our final prediction correctly predicted a Conservative victory with a substantial majority.
For this general election, we relied heavily on our own regression analysis of opinion polls. This was particularly important for this election because of the large changes in voter behaviour. As the 'Brexit election' many traditional Labour voters either stayed at home or defected to parties which were more definitive on Brexit. The Conservatives gained pro-Bexit voters in the North of England, and lost some pro-Remain voters in the South of England. Regression analysis was particularly useful in tracking these flows in advance, and was better than the simplistic uniform national swing method.
An interesting comparison of regression methods was possible by chance on 10 December 2019. On that day, both Electoral Calculus and another pollster published regression-based predictions. We used our tested methods which used a moderate sample size of about 6,000 GB voters. The other survey used a much larger sample size of 105,000 voters. But the predictions were very similar with only a one seat difference in the prediction for the number of Conservative seats (details).
The other innovative feature we used was to take the regression analysis as the "base-line" shape for the prediction to give the estimated shape of political support across all the seats. But we also allowed the absolute national level of political support to vary a little up or down, depending on the results of other public polls. This combination of geographic detail from the regression, plus a 'big picture' input from other polling, was helpful.
“We predicted the Conservatives would win 351 seats, which was closer to the actual result of 365 seats than any other final pre-poll prediction.”
Electoral Calculus made the most accurate pre-poll prediction of the result of the December 2019 General Election. Our final prediction correctly predicted a Conservative victory with a substantial majority. We predicted the Conservatives would win 351 seats, which was closer to the actual result of 365 seats than any other final pre-poll prediction (source Wikipedia).
Working with our partners, LucidTalk, in Northern Ireland, we also made a successful prediction of the result in Northern Ireland. Our predictions of party support were all within 2pc of their actual vote share. Our LucidTalk poll correctly predicted that the DUP and Sinn Fein would lose support compared with 2017 and that the Alliance would gain support. It also correctly predicted only small increases in support for the SDLP and UUP. In terms of seats, all but two seats were correctly predicted.
Full details of our 2019 predictions, and find out about our regression polling and election prediction services.
Electoral Calculus undertook a project to create a political segmentation of the UK voting population by political attitudes. This has become more relevant in recent years since the traditional single left-right axis no longer captures the reality of the public's political attitudes.
Electoral Calculus made vote share and seat predictions for the last elections from Britain to the EU Parliament in May 2019. We used our regression analysis of our own commissioned polls, on behalf of Remain United.