What do the polls really say about the referendum?

As we approach the final hours what are the opinion polls actually saying about the referendum?

There has been a lot of noise over the past few days about what the referendum polls are saying.  Professor John Curtice of Strathclyde University, who oversaw the accurate exit poll at last year’s general election, has summed up the situation as “we are in a cloud of uncertainty and people should absolutely look at the polls sceptically.”

The referendum will be a real test for the polling industry.  The industry as a whole had egg on its face after their failure to predict the Conservative general election victory. The similarity of the final projections meant that all of the major companies faced the same level of embarrassment.  This time it is different as there are widely differing projections.

ComRes which suggests an 8 point lead for Remain. Their projection included a squeeze question about views on the economic impact of leaving the EU which led to an adjustment of their projection by 1 percent towards Remain. Peter Kellner the former Chairman of YouGov has made a personal projection of an 8.5% lead for Remain

YouGov’s daily poll for the Times, published last night suggested a lead for remain of 1 percent. Well within the margin of error, so a statistical dead heat.

The final published poll is IPSOS Mori’s poll for the Evening Standard. It was undertaken by ‘phone on Wednesday night and it suggests a narrow 4 percent lead for Remain .

Against these polls suggesting the result going Remain’s way, we have had polls showing Leave ahead. Opinium suggested Leave is on 45 percent and Remain on 44 percent and TNS suggesting Leave on 43 percent and Remain on 41 percent.

There was a lot of movement in the financial markets earlier in the week on the back of suggestions that a there had been a shift of support towards remain. Final projections from ORB  published on Tuesday suggest that Remain might win by 54 percent to 46 percent. Their projection was adjusted for propensity to vote and the expectation that there will be some move towards the status quo when people vote Today.

YouGov’s projection, also published on Tuesday, brings together data from their recent polls and projections of trends.  It suggested has been a shift away from Leave since the start of last week, so prior to the murder of Jo Cox.

The methodology used for the projection not only considers different demographic groups in trying to develop their representative sample of the population, but also tries to adjust for the fact that different groups of people might have different views depending on where they live in the country.  YouGov’s projection was that, while there had been a move towards Remain over the past week and a bit, it might not be enough andLeave might win by 51% of the vote. As theyadmit, statistical uncertainty means that they cannot be very confident of that result: the model puts a 95% chance of support for Leave between 48 and 53.

There has been a continuing gap between ‘phone polls and polls undertaken online, with ‘phone polls suggesting stronger support for Remain than online polls. All the final ‘phone polls have Remain ahead with on-line polls suggesting that the race is neck and neck or that Leave is ahead. There are constant debates about the pros and cons of each methodology and the different sample bias (different people being more or less likely to be contactable by either method).

The betting markets seem to suggest that the most likely result will be a Remain vote with punters giving it about a 86 percent chance of winning, up from about 75 percent earlier in the week. This suggests that the markets have more confidence in ‘phone polling over online polling. The betting markets have been wrong in the past, including at the 2015 General Election.

There will be no broadcast exit poll tonight because of concerns about accuracy. There are suggestions that hedge funds have commissioned private polls so we might begin to see some shifts on the currency markets later today depending on where these polls suggest the vote is going. There is no guarantee that these polls will be accurate.  The markets as well as the public will have to wait until tomorrow morning to be sure of the result.

The first indications of the way that things are going will be between 12:30 and 1am and the first results come in. If the race is tight it will be later in the morning before the results a clear. We should have a good idea of the final results between 4-6am when we will have seen the results from most of the UK’s major cities