How Messenger chats factor into what you see in Facebook news feed

How often you chat with someone using Facebooks Messenger app is a signal the company uses to determine how to place posts in your feed. If you havent chatted with someone in a while on Messenger, and then you start chatting again, posts from that person might appear higher in your news feed.

That was one piece of information shared by Facebook engineers during a session Wednesday during the companys F8 conference in San Francisco.

The algorithm Facebook uses to rank posts in peoples news feeds is a complicated one, and it's always in flux, but the session, titled "How News Feed Works," shed light on it.

If a user shares location data with Facebook, that is also taken into account. For example, posts of friends who are geographically near may get more prominent placement, said Lars Backstrom, news feeds engineering director.

However, the users interests and his or her history of activity on Facebook likely carry more weight, he said.

A user's news feed contains every post from every friend, but Facebook places what it considers the most important entries higher, according to the engineers.

Some posts from Pages, however, may not always appear in users news feeds, if the posts don't generate a lot activity on the site or if they're overly promotional.

Another signal used for news feed ranking is how you watch and interact with video on Facebook, particularly videos that play automatically. Facebook began making videos that are shared natively on Facebook play automatically in 2013.

How long users spend watching auto-playing videos is a signal that Facebook is working to use to determine video placement, the engineers said. This type of information is vital to the marketers who advertise with video on Facebook.

Facebook has made several big changes to its news feed ranking algorithm over the past year, including a reduction of click-bait and of misleading posts or hoaxes.

Overall, some of the most important signals Facebook uses for its news feed ranking include the author of the post, the activity around it, and the type of content it includes, like a photo versus text. Photos tend to rank higher.

Zach Miners covers social networking, search and general technology news for IDG News Service. Follow Zach on Twitter at @zachminers. Zach's e-mail address is zach_miners@idg.com