Brexiteers shout the loudest on Twitter

Over the past month, CASM have worked with ITV’s Peston on Sunday program to take a look at how UK politics is being discussed on Twitter. As the two EU referendum campaigns gather momentum ahead of the 23rd June, we took a closer look at what Remainers and Brexiteers were focusing on.

Since early February we have collected all the tweets sent to or from UK MPs. Over two weeks (20th May – 2nd June, so a couple of weeks ago now), we narrowed the data down to look at the 100,000 tweets sent containing EU referendum hashtags.

It goes without saying that the referendum is the hottest topic in UK politics right now. You can’t open a newspaper or switch on the television without finding the latest on both sides’ campaigns, and Twitter is no different. Last week saw 54,000 tweets sent on these hashtags mentioning MPs, a 10,000 increase on the week before.

Who’s responsible? It’s the Leave campaign. For every tweet sent in favour of remaining, three are sent by Brexiteers. Whether a tweet was pro- or anti- Brexit (or something else) was identified with the help of an NLP (Natural Language Processing algorithm) operating at 70% accuracy across the three categories. The use of these classifiers isn’t perfect, but do tend to be pretty accurate over very large datasets. That means they can help us understand the broad patterns of conversations (although not all of the fine nuances of course). With that caveat in mind, are the two sides focusing on the same thing?

We had a hunch that while Remainers were emphasising the economic arguments for staying in the EU, Brexiteers were keener to stress the arguments around immigration and sovereignty. We built another algorithm to identify the subject of a tweet: was it about the economy, immigration, sovereignty or something else?

The algorithm performed well – 77% accurate across the four categories – and the results were interesting. If we exclude all the ‘Other’ chatter (around half the tweets), here’s what happened:

This data suggests that, indeed, there was a narrowing of focus in both camps. Economy became even more central to Remain’s campaigning, while sovereignty and immigration took centre stage for Brexit. If these are indeed the key battlegrounds, there is no doubt that both Leave and Remain are picking their battles.

What does this mean for the referendum? It’s well known that Twitter is no proxy for public opinion: those who message our MPs in their thousands tend to have their minds made up. But it does offer an interesting window into those activist groups. Brexiteers are shouting the loudest on Twitter, and those arguing both sides’ cases are closely tuned to their campaigns’ strongest arguments.