This week, Facebook CEO Mark Zuckerberg once again appeared before Congress, facing questions about how the massive social media platform that he created affects America’s political culture, and vice versa.
Thanks to an extensive study that includes four years of browsing data from 200,000 users on Facebook, Reddit, Twitter and online news sites, three University of Virginia professors have some answers.
Analyzing opt-in user data from 2012 to 2016, Brent Kitchens, Steven L. Johnson and Peter Gray, all faculty members in UVA’s McIntire School of Commerce, found that all three social media sites connect their users to a more diverse range of news sources than they would otherwise visit. However, Facebook tends to polarize users, particularly conservative users, more than other social media platforms.
In fact, the researchers found that typical conservative users, in months when they visited Facebook more than usual, read news that was about 30% more conservative than the online news they would typically read. Users who visited Reddit more than usual, on the other hand, read news that was about 50% more moderate than what they would typically read.
“We found that Facebook had a polarizing effect, Reddit had a moderating effect and Twitter did not have a significant effect” on the types of news people consume, Kitchens said, noting that the study came before Twitter changed the algorithm it uses to build its feed in 2016.
Their findings, which will be published in a forthcoming peer-reviewed article in MIS Quarterly, have already received a lot of attention on The Washington Post, where the professors contributed an op-ed, and other news sites.
The key difference, they say, comes down to how each site structures the algorithm that determines what news users see when they log on. Though it doesn’t share its data publicly, Facebook ostensibly bases its algorithm on “engagement,” or the number of likes, comments and shares a post garnered. Reddit is more topic-based, as users opt in or opt out of various discussion boards based on topics they are interested in. Twitter, until 2016, was purely chronological, showing news as it became available.
“On Facebook, inflammatory content tends to drive the most engagement, because it elicits emotion,” Kitchens said. The algorithm rewards that emotion, which can drown out more moderate posts and amplify more extreme ones.
That phenomenon holds true for both conservative and liberal users, but Kitchens, Johnson and Gray theorize that the effect is stronger for conservative users because they tend to turn to a large network of right-leaning sites while eschewing more moderate “mainstream media.”
“The echo chamber effect was definitely present for both conservatives and liberals, but more pronounced for conservatives,” Kitchens said. “This could be because of the landscape of news outlets at that time, with more liberal-leaning sites clustered at the center or on the moderate left,…
Read More: Study: How Facebook Pushes Users, Especially Conservative Users, Into Echo Chambers