False news spreads substantially faster on Twitter than real news does, a study by the Massachusetts Institute of Technology (MIT) has revealed.

Researcher Sinan Aral, a professor at the MIT Sloan School of Management and co-author of the study, said he and his colleagues found that false news defuses significantly farther, faster, deeper, and more broadly than the truth, in all categories of information, and in many cases by an order of magnitude.

Surprised and stunned

Deb Roy, an associate professor of media arts and sciences at the MIT Media Lab, who is also a co-author of the study said: “These findings shed new light on fundamental aspects of our online communication ecosystem,” adding that the researchers were “somewhere between surprised and stunned” at the different trajectories of true and false news on Twitter.

Moreover, the scholars found the spread of false information is essentially not due to bots that are programmed to disseminate inaccurate stories. Instead, false news speeds faster around Twitter due to people retweeting inaccurate news items.

Soroush Vosoughi, a co-author of the new paper, said: “When we removed all of the bots in our dataset, the differences between the spread of false and true news stood.”

The study provides a variety of ways of quantifying this phenomenon. For example, false news stories are 70% more likely to be retweeted than true stories are. It also takes true stories about six times as long to reach 1,500 people as it does for false stories to reach the same number of people. When it comes to Twitter’s ‘cascades’, or unbroken retweet chains, falsehoods reach a cascade depth of 10 about 20 times faster than facts. And falsehoods are retweeted by unique users more broadly than true statements at every depth of cascade.

The paper, “The Spread of True and False News Online,” is published today in Science.

The origin of the study involves the 2013 Boston Marathon bombings and subsequent casualties, which received massive attention on Twitter.

Vosoughi said: “Twitter became our main source of news.” But in the aftermath of the tragic events, he added, “I realised that a good chunk of what I was reading on social media was rumours. It was false news.” Subsequently, Vosoughi and Roy – Vosoughi’s graduate advisor at the time – decided to pivot Vosoughi’s PhD focus to develop a model that could predict the veracity of rumours on Twitter.

After consultation with Aral – another of Vosoughi’s graduate advisers, who has studied social networks extensively – the three researchers decided to try the approach used in the new study: objectively identifying news stories as true or false, and charting their Twitter trajectories. Twitter provided support for the research and granted the MIT team full access to its historical archives. Roy had served as Twitter’s chief media scientist from 2013 to 2017.

To conduct the study, the researchers tracked roughly 126,000 cascades of news stories spreading on Twitter, which were cumulatively tweeted over 4.5 million times by about 3 million people, from the years 2006 to 2017.

To determine whether stories were true or false, the team used the assessments of six fact-checking organisations (factcheck.org, hoax-slayer.com, politifact.com, snopes.org, truthorfiction.com, and urbanlegends.about.com), and found that their judgments overlapped more than 95 percent of the time.

Of the 126,000 cascades, politics comprised the biggest news category, with about 45,000, followed by urban legends, business, terrorism, science, entertainment, and natural disasters. The spread of false stories was more pronounced for political news than for news in the other categories.

The researchers also settled on the term ‘false news’ as their object of study, as distinct from the now-ubiquitous term “fake news,” which involves multiple broad meanings.

Novelty value

The bottom-line findings produce a basic question: Why do falsehoods spread more quickly than the truth, on Twitter? Aral, Roy, and Vosoughi suggest the answer may reside in human psychology: We like new things.

Aral said: “False news is more novel, and people are more likely to share novel information. And on social networks, people can gain attention by being the first to share previously unknown (but possibly false) information. Thus, as Aral puts it, “people who share novel information are seen as being in the know.”

The MIT scholars examined this ‘novelty hypothesis’ in their research by taking a random subsample of Twitter users who propagated false stories, and analysing the content of the reactions to those stories.

Vosoughi said: “We saw a different emotional profile for false news and true news. People respond to false news more with surprise and disgust. Meanwhile, true stories produced replies more generally characterised by sadness, anticipation and trust.

So while the researchers “cannot claim that novelty causes retweets” by itself, as they state in the paper, the surprise people register when they see false news fits with the idea that the novelty of falsehoods may be an important part of their propagation.

The researchers agree it is important to think about ways to limit the spread of misinformation, and they hope their findings will encourage more research on the subject.