# How does facebook rank news feed?
## Key moments of Facebook Algorithm
## EdgeRank
Stopped since 2011, replaced by Machine Learning with 100K factors.
## How the New Facebook Algorithm Works
The new Facebook algorithm works by ranking all available posts that can display on a user’s News Feed based on how likely that user will have a **positive reaction**.
Facebook’s algorithm for ranking and displaying content on your News Feed is based on four factors:
1. The **Inventory** of all posts available to display.
2. **Signals** that tell Facebook what each post is.
3. **Predictions** on how you will react to each post.
4. A **Final Score** assigned to the content based on all factors considered.
The process is based on the [Vickrey-Clarke-Groves algorithm](https://en.wikipedia.org/wiki/Vickrey%E2%80%93Clarke%E2%80%93Groves_auction), which “operates as a [closed auction](https://medium.com/@freeformers_uk/digital-uncovered-4-facebook-ad-auctions-c5a8a58f7a42),” in which advertisers’ bids are kept hidden from one another, prompting them to bid their real value.
## The New Facebook Algorithm
The new Facebook algorithm works by prioritizing content posted from friends over publishers, with a focus on “meaningful interactions.”
Since the [data controversy](https://tinuiti.com/blog/2018/03/facebook-messenger-apps-under-review-following-cambridge-analytica-data-disaster/) erupted around the social network in late 2017, Facebook has worked to improve transparency around how it ranks content on the News Feed.
Between Facebook’s F8 [conferences](https://tinuiti.com/blog/2018/05/facebook-f8-2018/), News Feed [webinars](https://www.forbes.com/sites/paularmstrongtech/2018/02/03/what-you-should-know-from-facebooks-private-newsfeed-webinar/#181acac3452d), and algorithm [presentations](https://www.youtube.com/watch?v=94s0yYECeR8) — we can now say that Facebook’s new algorithm is no longer a complete black box.
Facebook went public with changes to the algorithm in their post “Meaningful Interactions” [update](https://newsroom.fb.com/news/2018/01/news-feed-fyi-bringing-people-closer-together/) back in January 2018.
## The 4 Facebook Algorithm Factors
The goal of Facebook’s algorithm is to “show stories that matter to users,” according to Adam Mosseri, VP of Facebook’s News Feed Management. With that in mind, you should know how Facebook’s different algorithm factors work together to determine which stories “matter” to a user.
### Inventory
Inventory represents the stock of all content that can display to a user on Facebook’s News Feed.
This includes everything posted from friends and publishers.
### Signals
Signals represent the information that Facebook can gather about a piece of content.
**Signals are the single factor that advertisers have control over**. These are your inputs that Facebook interprets; type of content, the publisher, its age, purpose, and more.
You want your content to signal to Facebook that it’s meaningful and relevant to your target audience.
### Predictions
Predictions represent the behavior of a user and how likely they are predicted to have a positive interaction with a content piece.
### Score
Score is the final number assigned to a piece of content based on the likelihood the user will respond positively to it.
### Meaningful Interactions Are Valued Most
As advertisers, the only part of the process that we have control over are the signals of our content.
These signals can be divided into two categories: **passive** and **active**.
**Passive** signals include view time, story type, time posted, and other metrics non-active metrics.
**Active** signals include likes, shares, comments, and other active events that prompt engagement.
You should tailor your content to promote positive engagement, or what Facebook has defined as “meaningful interactions.”
### Why Should Advertisers Care?
* 4.75 billion pieces of content shares – daily
* 300+ million photo uploads – daily
* 510,000 comments – every 60 seconds
* 293,000 statuses – every 60 seconds
## Reference
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