by Stephen Fisher and Alan Renwick.

The small shift towards Remain in the polls that we observed last week has been reversed. Setting aside Don’t Knows, our polling average for Remain has dropped back from 53% to 52%. Despite there being little difference between the headline figures for yesterday’s ICM phone and online polls, our estimate (and corresponding adjustment) for the typical difference between the two modes of interviewing has barely changed.

The one-point drop in our polling average has led to a corresponding one-point drop in the forecast share of the vote for Remain, from 55% to 54%. The 95% prediction interval surrounding this estimate has again narrowed very slightly to ±12 points. So we are now forecasting that Remain will win between 42% and 66% of the vote.

Overall the probability that the Remain vote will be larger than the Leave vote has dropped from 79% last week to 73% now. Continue reading Forecast update for the Historical Referendums and Polls based Method →

by Stephen Fisher and Alan Renwick.

There has been a small shift towards Remain in the polls over the last two weeks. Excluding Don’t Knows, our polling average for Remain has moved from 52% on 10th May to 53% now. This figure is based on the most recent polls from each of seven companies: one from each but two from ICM (one by phone and one conducted online). The Remain share has been adjusted down by 2.15 points for telephone polls and up by the same amount for online polls to account for the relatively stable gap between these different methods in the levels of support they tend to give the two sides.

Using the historical experience of referendum polls and referendum outcomes in the UK and on the EU elsewhere, as discussed here, our latest forecast is for Remain to win 55% of the vote in a month’s time. The 95% prediction interval surrounding this estimate has narrowed very slightly to ±12.5 points. So we are forecasting that Remain will win between 43% and 68% of the vote.

Values closer to the middle of this range are more likely. Overall the probability that the Remain vote will be larger than the Leave vote is now 79%, up from 72% two weeks ago.

by Stephen Fisher and Alan Renwick.

We have published two previous forecasts of the result of the UK’s referendum on EU membership, which are based on current vote intention opinion polls for this referendum and on the historical experience of referendum polls and referendum outcomes in the UK and on the EU elsewhere. The main ideas behind this approach are set out here. This post offers an update. Continue reading An Update on the Historical Referendums and Polls based Forecast →

by Stephen Fisher and Alan Renwick

A month ago we issued our first forecast for the EU membership referendum on 23rd June 2016. Based on an analysis of referendums in the UK and on the EU outside the UK, and on vote intention opinion polls we forecast that Remain had an 87% chance of winning, and that Remain would get 58% of the vote, plus or minus 14. This was in part based on our polling average (excluding Don’t Knows) of 55% for Remain on 11th March.

Our current forecast suggests the contest is a fair bit closer. Our polling average now puts Remain on 52%. We now give Remain a 73% chance of winning and estimate that the Remain share of the vote will be 54% plus or minus 13 points.

The key change here is the drop from 55% to 52% Remain in the polling average. The main reasons for this are as much or more methodological than substantive. Continue reading Second forecast for the Brexit referendum →