Facebook is once again tweaking its News Feed algorithm — this time, to include a factor that it says will predict how long you spend looking at an Instant Article or a post within the Facebook mobile browser. The goal is understand which stories it should surface in your News Feed to keep you more interested in reading. Facebook explained that this update “only factors in the time people spend reading an article, regardless of whether that time is spent reading an Instant Article or an article in the mobile web browser.”

The company is also looking at ways to reduce how often you’ll see multiple posts from the same source within your News Feed.

With the enormous amount of time we spend within Facebook’s News Feed, fine-tuning the ranking algorithm is a major challenge. If successful, it will allow the social network to provide us with the appropriate content at the right time instead of simply listing articles in chronological order. Some of the adjustments that have been made include tallying how much time you spend reading a post within the News Feed, regardless of whether that article was opened or not. Facebook also added in the ability to account for how often you click on an article and then come back to the News Feed, using that as a signal that the content may not have been in line with your expectations. It also looked into articles that you are likely to actually engage with.

By factoring in how long you’ll spend reading an article within the mobile browser or Instant Article, Facebook is also looking out for publishers and advertisers. With Instant Articles now available to all publishers, Facebook likely wants to get more people using it — with greater adoption comes more impressions for articles and the ads that are featured.

The News Feed updates have already started rolling out and will continue to do so over the coming weeks. Facebook doesn’t think Pages will see “any significant changes,” but cautions that some users may see a “small increase in referral traffic,” while others could see “minor decreases.”