Stephen Fisher and Alan Renwick have developed a method for forecasting the outcome of the EU referendum based on current vote intention polling and analysis of opinion polling from previous referendums in the UK and across Europe. The probability of a Remain win is now 52 per cent.
Our polling average now has Remain at 49 per cent after setting aside don’t knows.
From this we forecast Remain to get 50 per cent of the vote.
The 95 per cent prediction interval is only a little narrower than ±12 points. So Remain are forecast to win between 39 per cent and 62 per cent of the vote.
The probability that Remain will win the referendum is now 52 per cent.
The methods behind our forecast
The method behind this forecast is based on the historical experience of referendum polls and referendum outcomes in the UK and on the EU elsewhere, as discussed here.
Our polling average is constructed by taking the most recent poll from each company within the last two weeks. If a company uses both phone and online modes then both the most recent phone poll and most recent online poll are used. This applies to BMG, ICM and ORB this week. The current average is based on the results of twelve polls from nine companies, of which six were conducted by phone and six online. All polls are adjusted to account for the tendency for phone polls to be more favourable to Remain. This is done by adding 1.75 to the Remain share for online polls and subtracting the same amount for phone polls.
This post was originally published on Elections Etc. and is re-posted with permission.
About the authors
Dr Stephen Fisher is an Associate Professor in Political Sociology and the Fellow and Tutor in Politics at Trinity College, Oxford.
Dr Alan Renwick is the Deputy Director of the Constitution Unit.
The Constitution Unit Blog 
I am very interested in your predictions.
How different is this very polarising vote … in or out ….. from an election type vote where there is probably more confusion with many options but importantly get out clauses by deliberately voting for a party you know won’t win.
the only get out clause in this instance is by not voting. Do you use the same method of calculations for both types of scenarios.
I travel the country and get a feeling, completely overwhelming, for the leave voters. When in an area that is not overwhelming there is a balance. but never favouring the remain vote. Yet most of the polls are averagely balanced. It just does not seem to fit. I ask everyone I meet. You don’t seem to do that in an election scenario but for some reason it is alwright to in this case …people don’t seem to mind