by Ailean Beaton

UK pollsters came into this General Election under a huge cloud of scepticism. Their failure to anticipate the Conservative victory in 2015 left the industry in crisis and carrying out an internal investigation into what went wrong. This time – with one or two exceptions – the result was even worse although there won't be any introspection or self-flagellation.

Despite their repeated failings opinion polls are still incredibly influential over the tone of media coverage and the decisions politicians make. Indeed its probably there would not have been an election but for Theresa May’s reliance on the huge lead she was projected to have in the polls.

It was clear long before the results were in on Friday morning that there was going to be egg on a number of pollster' faces. In the early days of the campaign the polls were unanimous in giving the Tories a huge lead over Labour, by a fortnight before polling day the projections varied massively from company to company.

“The criticism that was made after 2015 was that too many of the polls were too similar to one another and perhaps that they were copying each other a bit too much.” says Professor John Curtice, president of the British Polling Council (BPC) and politics professor at Strathclyde University. “That’s certainly not an accusation that can be made this time.

“The polls were pretty close on estimating the Tories but underestimated Labour and so insofar as there was a polling miss it was a miss in the opposite direction to the one that usually happens.”

The big polling companies – IpsosMORI, Panelbase, YouGov, ComRes and newcomer Survation – all predicted the same general result, a Tory victory, but all to radically different extents.

Each polling company uses different combination of gathering techniques (over-the-phone, in person or online surveying) and each has a different methodology. One of the new additions for many of the polling companies is to factor in the ‘shy Tory effect’ – the very thing that contributed to the 2015 upset, caused by many Conservative voters not being forthright in declaring their voting intention. Most of the 2017 polls took this into account, to a greater or lesser extent.

Based on the actual outcome of the election it was only the Survation polls that were anywhere near accurate. Even Labour’s own BMG had the party pegged for a wipe-out.

If the Tory vote was underestimated in 2015, it was the youth vote that was neglected this time.

According to findings by Tory pollster Lord Ashcroft the real dividing line was not class but age. Two-thirds of young voters (under the age of 24) said they had voted for Labour.

We won’t have accurate figures for young voter turnout until later this week but informed estimates say upwards of 60 per cent voted, whereas in 2015 it was around 40 per cent.

There have been calls from the media and politicians to change the way opinion polls are reported, including banning them in the days before an election, as countries like France have done.

The pollsters themselves recognise this feeling, as Curtice admits: “I think quite clearly because of the way people felt they got burned in 2015 media use of the opinion polls was much more limited this time around – actually there were fewer polls conducted overall.

“There was initially a greater reluctance to report them. What happened during the election is that many journalists perceived that Theresa May wasn’t campaigning very well and that Jeremy Corbyn was doing relatively well, so that when they saw their perceptions being confirmed by the trends in opinion polls [when they narrowed] then, towards the end, there was greater attention paid to them.”

There will not be large-scale industry inquiry into this new failure, but the BPC has asked its members to present a report on what they’ve learned at a conference just before Christmas.