British Election Study release their campaign data

The British Election Study have released their data from the election campaign waves today - one large wave straight after the election was called, a wave of daily rolling polls from throughout the campaign itself and a third large wave conducted straight after the campaign. All three of these datasets were collected online by YouGov (the face-to-face element of the BES is still to come). If you're au fait with stats software like SPSS, Stata or R the raw data is available for download on the British Election Study site here.

There's already some analysis of the data by the BES team here (a longer version of the article you may have seen on BBC this morning), focusing on how people changed their votes between 2015 and 2017, and between the beginning and end of the election campaign.

The article breaks down 2015 vote by Remainers and Leavers. Looking at how 2015 voters who backed Leave ended up voting in 2017, the Conservatives kept the vast majority of their 2015 leave voters and picked up over half of the 2015 UKIP vote (as well as a chunk of Labour Leavers). The collapse of UKIP wasn't all to the Conservatives' favour though, 18% of UKIP Leavers ended up moving to Labour.

Turning to the Remain vote, Labour were the clear victor: around a third of 2015 Tories who voted remain drifted away from the party, either to Labour or to the Lib Dems, but Labour also picked up a chunk of the 2015 Lib Dem vote and most of the 2015 Green vote. Of course, while this is easy to view through the prism of Brexit, that doesn't necessarily mean Brexit was the main driver (to give an obvious example, yes - a large proportion of Green Remain voters moved to Labour... but a large proportion of the 2015 Green vote had already moved to Labour before the referendum, presumably as a result of the direction Jeremy Corbyn had taken the party).

More interesting is the movement during the campaign itself. 19% of people changed how they would vote between the start and the end of the campaign. This is not in itself unusual - in 2015 the figure was 17%, and according to the BES team it was higher in 2010 and 2005. The difference in 2017 is that this movement was overwhelmingly in favour of the Labour party, whereas at previous elections the churn largely cancelled itself out. Hence during the campaign we can see significant numbers of Tory votes, Lib Dem voters and, most of all, don't knows moving towards Labour, but very little movement away from Labour.

In terms of explanations for the movement - while the voters Labour attracted during the campaign were those you'd expect to be the most receptive (that is, tending to be opposed to a hard-Brexit and left-leaning), the most obvious movement was on leadership ratings, that sharp collapse in Theresa May's ratings and the steady increase in Jeremy Corbyn's, and those people who moved to Labour during the campaign were also those who displayed the biggest increase in their perceptions of Jeremy Corbyn.

Ed and Chris's full article is here.