Facebook's News Feed algorithm is developed by Facebook to govern what is displayed and how high on the News Feed
Facebook uses an elaborate algorithm to determine what is displayed within the news feed. The news feed algorithm does not have an official name, however it is popularly is referred to as "EdgeRank", the original name of the algorithm that determined the news feed.
EdgeRank was originally built up of 3 components: Affinity, Weight, & Time Decay. These components are still important factors in ranking the news feed. Most announcements of changes are simply variations of one of the three original components.
Understanding how EdgeRank was computed helps shed invaluable insight into the news feed algorithm of today.
Affinity is a one-way relationship between a User and an Edge. It could be understood as how close of a "relationship" a Brand and a Fan may have. Affinity is built by repeat interactions with a Brand's Edges. Actions such as Commenting, Liking, Sharing, Clicking, and even Messaging can influence a User's Affinity.
Weight is a value system created by Facebook to increase/decrease the value of certain actions. Commenting is more involved and therefore deemed more valuable than a Like. In the weighting system, Comments would have a higher value than a Like. In this system all Edges are assigned a value chosen by Facebook. As a general rule, it's best to assume Edges that take the most time to accomplish tend to weigh more.
Time Decay refers to how long the Edge has been alive; the older it is the less valuable it is. Time Decay is the easiest of the variables to understand. Mathematically it is understood as 1/(Time Since Action).
As an Edge ages, it loses value. This helps keep the News Feed fresh with interesting new content, as opposed to lingering old content.
Facebook users, on average, could be shown nearly 1,500 stories every visit to the news feed. Facebook's news feed algorithm is an evolved version of EdgeRank. The news feed algorithm possess many different facets for each variable these days.
A post's news feed value is influenced by both global and personal interactions. When an object begins to pickup engagement, each action has impact on the value of the post. For some people, they will not have any personal connection to the post, but will still be shown it due to global popularity. Having a personal connection to the post (think a friend commenting on a brand you both are fans of), will increase the likelihood of it appearing in your news feed.
Facebook examines which post types a user typically engages with. If a user engages frequently with only photos, Facebook will begin to show more photos. Facebook even monitors this choice with individual Pages. If you engage with Page A's photos and Page B's links, you'll see more of photos from Page A and more links from Page B.
For brands, it's imperative to understand which content types your fans are most interested. It should be noted, that it's different for each fan, however you should be able to tease out overall averages for your types of fans.
Facebook analyzes each story within their system and analyzes it by examining the likelihood a user is to engage with a post or hide it. If the equation is net positive, they'll show it in the news feed.
Engaging with Sponsored Posts will increase the Affinity between the user and the Page. This is great news for brands advertising on Facebook. This provides additional value down the line from Organic content.
Facebook stated in an interview with Marketing Land that the news feed algorithm is even influenced by the "different devices they might be using when they're on Facebook."
For brands with highly mobile audiences, understanding how browsing on a mobile device impacts engagement is imperative. Mobile users who commute, may be less likely to consume video content due to long load times. Mobile users may also be less likely to engage with links, as they most likely do not have as much time to read content. Understanding these subtleties can improve a brands opportunity for exposure in the news feed.
Story Bumping is a Organic Ranking signal. Each visit, Facebook looks at all of the new content and creates corresponding scores. A Post decays on average after about 3 hours because of Time Decay. Therefore most people's news feeds lack old content. With Story Bumping, objects with high values (and assumably now very low values of Time Decay) can be bumped into your feed if you "missed the update". This update to the News Feed algorithm ultimately decreases the effect of Time Decay.
Facebook keeps track of who a user has made the last 50 interactions with. People & Pages that have been interacted with these last 50 interactions, will receive a small bump in value (Affinity). Ultimately, these interactions are now having a stronger influence into the Affinity component.
Facebook recommends to "create and publish a variety of interesting content that will attract Likes, Comments, & Shares. That requires understanding your Facebook fans".
Understanding your Facebook fans takes a few different approaches to achieve success. How often are they using mobile devices? When are they online? What content creates engagement? What else in the news feed is taking their attention?
We recommend doing as much A/B testing as possible. A/B testing provides an opportunity to segment out oddities in your fan's behavior. Learn how to word and craft your content, discover timing strategies, and delivery methods.