Truth decayFacebook’s war on fake news is gaining ground

Published 19 September 2018

In the two years since fake news on the Internet became a full-blown crisis, Facebook has taken numerous steps to curb the flow of misinformation on its site. Under intense political pressure, it’s had to put up a fight: At the peak in late 2016, Facebook users shared, liked, or commented on an estimated 200 million false stories in a single month. A new study is shedding light on a key question: Are Facebook’s countermeasures making a difference?

In the two years since fake news on the Internet became a full-blown crisis, Facebook has taken numerous steps to curb the flow of misinformation on its site. Under intense political pressure, it’s had to put up a fight: At the peak in late 2016, Facebook users shared, liked, or commented on an estimated 200 million false stories in a single month.

Now, in one of the first studies of its kind, Stanford economist Matthew Gentzkow is shedding light on a key question: Are Facebook’s countermeasures making a difference?

It looks like they may be, according to findings detailed in a new working paper by Gentzkow and co-authors Hunt Allcott and Chuan Yu.

From December 2016 to July 2018, Facebook user interactions with content from sites flagged as producers of false stories fell 65 percent. Over the same period, engagement with these same stories on Twitter actually rose, suggesting that the trend did not simply reflect declining interest in such stories or declining production by those sites. And the timing of the drop in engagements coincided with changes by Facebook such as updating its news feed algorithm, moving to block ads that promote deceptive content, and instituting a fact-checking program.

“These patterns suggest Facebook’s efforts to limit the spread of misinformation among its users may be having a meaningful impact,” says Gentzkow, an economics professor and senior fellow at the Stanford Institute for Economic Policy Research (SIEPR).

Gentzkow’s study is especially timely with the midterm elections less than two months away. The role that fake news sites may have played in 2016 voting is at the heart of a federal investigation, several new state laws and plenty of public hand-wringing. Earlier this month, executives from Facebook and Twitter testified before Congress for the third time in less than a year as part of its inquiry into election meddling by Russia and other foreign groups.