Few academics have their statistical models exposed to such searching – and potentially nightmarish – scrutiny as those who work on the UK’s general election exit poll. John Curtice, the public face of the experts who produce the prediction, had a “disturbing” moment as early results came in, but ultimately the exercise was proved highly accurate as it “surprised the world” once again.
The exit poll predicted correctly that the Conservatives would fail to win a majority, estimating that they would win 314 seats. As it turned out, they won 318.
Asked whether he was pleased by the poll’s performance, Professor Curtice, professor of politics at the University of Strathclyde, said that “relieved” might be another word to describe it. “You’re only as good as the last one you did,” he added.
For this snap election, an exit poll “usually planned over six months had to be mounted in six weeks”, so the number one rule in preparing was “don’t change anything unless you have to”, he said.
It was, said Professor Curtice, who once again was on-screen throughout the night during the BBC’s coverage, “the same methodology that in 2015 also surprised the world by saying, ‘Hang on, it’s not close, the Tories have won quite easily.’ Or indeed in 2010 when we said, ‘No, no, the Liberal Democrats haven’t got more seats, they’ve got fewer.’ So it defies the conventional wisdom every time – which just goes to show you the conventional wisdom ain’t too good.”
Once the first handful of results were in from the North East, former YouGov president Peter Kellner suggested that the exit poll had underestimated Tory support and that a huge majority was still possible for Theresa May.
As Professor Curtice had assistants “scour the internet” for information on how other seats looked and reporters in the studio passed on information, he quickly became aware of the likelihood that Labour would perform more strongly elsewhere.
“There was a moment, which I think has been clipped [online], where I say, ‘We should hold our nerve here.’ That’s because I knew of the side information,” Professor Curtice said.
Although analysis on the student vote is yet to be carried out, he said that “what we do know is that young people in general voted very strongly for Labour…We also know that [support] increased markedly during the campaign.”
He suggested that the Labour leader, Jeremy Corbyn, had been “picking up a concern that life is tougher for younger people – it’s more difficult to get a job; it’s more difficult to get a house and get into the housing market; it’s bloody expensive to go to university if you do have the luck to go to university.
“The Conservatives did put together a coalition of Leave voters, but it wasn’t enough because in some cases they were losing ground among constituencies with lots of young people,” Professor Curtice added.