How would you determine how to rank posts in the newsfeed?

Facebook technical questions require this level of detail.

C: Okay, Are we discussing facebook newsfeed here or some other SN?

I: Facebook.

C: By Posts, i am inferring anything that appears on the newsfeed like photos, videos, memes, links, Ads etc.

I: Yeah, correct.

C: By ranking posts in the news feed, i am assuming that we focus on the order of posts in the news feed,ie, what appears first and what later. Am i correct?

I: Yeah, we want to look at the order.

C: Okay.Are we focussed on the newsfeed of a stable, old user or a new user cause the news feed may look different in the two cases?

I: Stable User.

C: Okay.

Now the User group is a stable, old User of Facebook.

Although there can be different personas of the users but we might want to make an algorithm that fits well with most of the users.

We may change the algorithm a little bit depending upon the User Groups and geography/demography and this can be a part of our experiments.

Now, lets first think what are the factors that determine the importance of the post to me as a user.

1. How close/good friend am i to the person whose post we have to rank?

2. How important is that post? 

3. What is the post type? Video/ link/ text/photo etc 

4. Is the post Recent/old?

5. How much other people have liked/reacted to the post?

6. For Ads, how relevant is the Ad to me as a User?

Lets discuss this one by one

1.  1. How close/good friend am i to the person whose post we have to rank?

I will want to see the post of a person who is a good friend in real life first in my news feed. The closest proxy to real life friendship is facebook engagement,ie if i engage with someone's posts regularly i am a close friend of that person and should be ranked higher in my news feed.

2. How important is that post?

Posts which are of an important life event like Convocation, Marriage etc. are very important posts and they should be propelled to the top of news feed as these signify an important life event.

3. What is the post type? Video/ link/ text/photo etc

Now, facebook has the data that as user, I like to engage more with a particular type of post, which maybe  videos or memes or links. Showing them first will capture more attention of the user and facebook would want to show them  first.

4. Is the post Recent/old?

Recent posts are more likely to be relevant as on today. Hence, it makes sense to show recent posts first. However, this should be seen in conjunction with other variables like Posts importance.

5. How much other people have liked/reacted to the post?

More engagement per post means more is the quality of that post. Its like a real time crowdsourced way to tell about a post's quality. Hence, the post that gets more likes gets a better Post Rank

6. For Ads, how relevant is the Ad to me as a User?

Now, showing Ads between posts is as much an Art as it is a science.

Lot of Ads will drive away the user. Very few Ads will mean less Revenue.

The important thing here is Relevance of the Ad to the User and his past Ad interactions.

Ads are less suitable for top of the news feed. They should be placed in between organic posts. But it is important to place Relevant Ads( coming from User's browsing behavior) shown first then other ads.

Now, the actual relative importance of the above logics can be part of an A/B/N experiment that aims to maximise user engagement and facebook revenue.

The relative weights may also depend on the demographic and country of the user. Eg. Certain country users enagage with Ads or Videos more than other countries etc.

This will an algorithm that will be always a work in progress and evolve itself to suit the goals of engagement and revenue.

Clarification questions: 

• Who am I ? The PM of newsfeed ? or ? … 

• What do we mean by “ranking “ ? is it the place of appearance ? is an internal engagement ranking ? or ?... 

• How would this ranking manifest ? 

• What do mean by Posts ? any content that is shared ? by any user ? or ?..

Let's pls quickly review the Newsfeed goals, metrics and users/actors, before we jump into solutioning ? 

Newsfeed is like the “BFF” of the user..  it's the homepage that brings to the user all of the content that the user is deemed to be interested in, know about, and benefit from. 

It’s a mature product, although it keeps learning all the time, and It serves practically all of FB users. 

To determine how we to start determining posts ranking in the newsfeed I’d like to focus on one user segment who (1) can potentially benefit the most from this logic, and (2) who would then be more engaged and delighted, hence bring positive impact to FB .

So user segmentation related to the newsfeed can take different shapes and forms, here are some examples (that are not mutually exclusive):

• By social connection intensity:

  • very.high.social.connected users (eg. 1000+ friends)

  • ... 

• By behaviour: 

  • very.highly.engaged.users (eg. users in the top 10% percentile of dau/mau)

  • Newsfeed.frequent.visitors (eg. users who spend in avg.20min on the feed, 7d/7d)

  • medium.level.engaged.fb.users_low.engaged.Newsfeed.users (eg. users who spend in avg.1min or less on the feed, 50% percentile of dau/mau)

  • …

• By demographics:

  • Millennials 

  • …

• By user lifecycle: 

  • New users 

  • Returning users

  • …

• By dominant device type:

  • Tablet users

  • Desktop users

  • …

I’d like to focus on medium.level.engaged.fb.users_low.engaged.Newsfeed.users, who are using mobile device since:

• They represent a big enough group (say between 9% to 11% of the overall MAUs). 

• The usage on the mobile platform is the most intensive one and there could be different considerations for content prioritization and viewing between the platforms. 

• The hypothesis is that if we can increase their engagement on the newsfeed we could increase their overall engagement.

What potential pain points could they have with regards to the newsfeed and the posts ?

1. They open the app with a clear intent (to go to groups, events, …) and thus are “blinded” to the newsfeed 

2. They might not find interesting posts in the very first glance at the screen 

3. They may not recognise the users who posts / comment / react , hence they might be reluctant to engage with the page

We can focus on problem 1 (newsfeed bliness) since it is very fundamental to make sure that these users are not blinded before taking further optimisation actions. 

If we’re discussing the logic / algorithm to use, and what data points to use, we can try the following solutions: 

solutions:

We can test some solutions for the hypothesis that “better ranked posts will increase newsfeed engagement for said user segment, while not negatively affecting their overall engagement and usage” 

1. embedding notifications messages in the newsfeed, to increase the frequency of visit to the feed 

2. prioritizing post that are based on- or sources to- their most engaging behavior/products on fb, for example, people who are heavy marketplace users would see more newsfeed posts from the marketplace with the objective of improving the marketplace experience thru newsfeed 

3. inviting them to take a dynamic survey where they will be asked to review the newsfeed and indicate what posts are - more / less valuable for them, to learn and to entice them to spend a bit of time on the newsfeed 

I’d like to focus on solution 3 (dynamic survey) since it is much less risky, in terms of cannibalizing other behaviours/products, it has medium level efforts, and it can create a big impact to our goal.   

The metrics for testing this solution with said user segment:

• newsfeed.engagement.KPI rate (blended metric including number of reactions, comments, shares, time-on-newsfeed, interactions, etc on the newsfeed)

• retention rate (7d, 14d) 

• DAU/MAU rate 

• …