The insight was published as part of the platform’s “Good Questions, Real Answers” series.
In a blog post, the site said that they use “two key factors” in determining which ads to show users.
“First, advertisers choose their target audience through our self-service tools. Audiences are created based on categories like age and gender, as well as actions people take on our apps such as liking a Facebook Page or clicking on an ad.”
“Next, when determining which ads to show someone, our system gathers ads that include that person in the advertiser’s chosen audience. These ads move to the auction stage,” it reads.
For each advert which reads the auction, Facebook chooses the top ads to show to a user based on ads with the highest “total value score”, which combines ad quality with advertiser value.
“We find advertiser value by multiplying an ad’s bid by the estimated action rate. This is an estimate of how likely that particular person is to take the advertiser’s desired action, like visiting the advertiser’s website or installing their app.
“We then add the ad quality score, which is a determination of the overall quality of an ad. We use machine learning to inform this process, as we explain below,” the post adds.
Ad Quality is also informed by responses from users, including how often an ad is reported or hidden.
“Low-quality attributes” are also assessed as part of ad quality, such as too much text in the image, sensationalised language or clickbait.
Facebook went on to point out that ads with the highest bids don’t always win auctions, saying that lower bids “often win” if the system finds that a person is more likely to interact with them, or that they’re of a higher quality.
The post concludes with the platform emphasising that they do not sell people’s data to advertisers, or share information with them which identifies specific people, unless permission has been granted.
Meanwhile content from text messages or a phone’s microphone does not inform ads, or affect what users see in their News Feed.
The full explanation can be found on the Facebook for Business website.