Facebook has announced it will prioritise news sources deemed to be more trustworthy on its News Feed.
The firm said the social network community would determine which outlets are reliable via the use of user surveys.
Founder and chief executive Mark Zuckerberg said news content would soon make up around 4% of what appeared in people’s News Feeds – down from 5% before.
The move is the latest attempt by the company to quell the spread of so-called fake news and propaganda on the network.
As part of that continuing battle, Twitter also announced on Friday that it had notified 677,775 US-based users who had retweeted, liked or followed Russian bot accounts on the network in the run up to the 2016 US presidential election.
The change is an attempt to shift the key judgements over bias and accuracy away from Facebook’s employees, and onto its user base.
“We could try to make that decision ourselves, but that’s not something we’re comfortable with,” Mr Zuckerberg said.
“We considered asking outside experts, which would take the decision out of our hands but would likely not solve the objectivity problem. Or we could ask you – the community – and have your feedback determine the ranking.”
Users will be asked, as they sometimes are about advertising, whether they recognise a news brand and if they trust it.
Facebook’s theory – yet to be tested on a large scale – is that while there are many partisan outlets that have readers that trust them, there is a smaller subset of media companies that a majority people find “broadly trustworthy”, whatever their particular leanings.
“There’s too much sensationalism, misinformation and polarisation in the world today,” wrote Mr Zuckerberg, who recently announced that his challenge this year was to essentially “fix” Facebook.
“Social media enables people to spread information faster than ever before, and if we don’t specifically tackle these problems, then we end up amplifying them.”
Winners and losers
The news ranking system will first be tested on US-based users only, and the results of the survey will not be made public.
“This is one of many signals that go into News Feed ranking,” a Facebook spokesman told the BBC.
“We do not plan to release individual publishers’ trust scores because they represent an incomplete picture of how each story’s position in each person’s feed is determined.”
As with any algorithm change, be it Facebook or any other major web service, there will be some that benefit and others that will struggle.
Facebook – the secret election weapon
Among the winners will likely be traditional media organisations with long histories or a strong broadcast presence, such as the New York Times or BBC.
However, emerging brands will suffer if recognition is not as strong, regardless of whether the content is trustworthy or not.
For instance, Buzzfeed’s initial beginnings as a viral site would have almost certainly hindered its growth into a serious news organisation had it been subject to the ideas about to be put in place by Mr Zuckerberg’s team.
Also, it is unclear how trustworthy, specialist news organisations with smaller readerships – such as science publications – will be treated under these rules, though Facebook’s head of News Feed Adam Mosseri said local news would at least be protected.
“We’re making it easier for people to see local news and information in a dedicated section.
“We’ll continue to work on ways to show more local news that is relevant to where people live.”