How do you define the goals and metrics for Facebook Newsfeed?

Defining goals and metrics for the Facebook Newsfeed. 

First, let's understand what the goals of the newsfeed. Newfeed is Facebook's landing page. When users log-in they see the Newsfeed as their first stop within Facebook. I know from my experience, you'll see your networks posts, event activity, news from pages you follow, ads and other relevant content. The goal of the Newsfeed is to help you keep updated on the recent (or not recent) activity that is happening in your network. Your network can consist of friends, places you follow, pages you follow (music artists, communities). 

When I think about metrics, I'll hone in on Facebook's motto which is connecting people from around the world to each other. Key metrics I feel like we should track when it comes to the Newsfeed are: 

1) Daily Active Users & Weekly Active users & Monthly active users 

2) Time spent on the newfeed from login to navigating away 

3) On average within a session on Facebook, what % of time do users return to the newsfeed 

4) Retention metrics such as: 7 day retention of users, 28 day retention of users 

5) Engagement in the newsfeed this would include: reactions, comments and shares in newfeed content. Reactions would include: likes, hearts, sad face, angry face etc. 

6) Click through rate for ads; this would help us understand whether ads are relevant 

7) Number of connections made through the newsfeed page; friend suggestions are displayed on the landing page. I would want to understand if those are helpful to users 

Description of the Product:

The Newsfeed is a key element for Facebook, as it is the page a user is taken to as soon as they log in. It has a scroll-through style that shows friend activity, relevant and recommended content, as well as advertisements. This is where the most action takes place, and was implemented in order that the user would not have to navigate to a specific friend's timeline to see what they have been up to. Rather, they can get a variety of information aggregated in one place.

Goals:

As with most FB products/features the goal is to promote user engagement.

Customer Journey:

The journey is simple as mentioned above: once the use logs on, he is immediately taken to the Newsfeed. Hence, we can neglect awareness, acquisition, and activation (since we can readily assume the user has already registered an account) to focus on engagement and retention.

Metrics:

• For engagement, I think the main thing we can measure the average number of interactions a user has per visit to the Newsfeed. That is, how many times they like, comment, share, or post content per visit. We can perhaps break this down further to see which type of interaction is most prevalent. This is useful to gauge the how the presented content captivates the user - it could be a sign of how well the algorithm that determines relevance/recommendations is performing.
• We can also measure the average time users spend on the Newsfeed. A limitation to this is measure is if the user is idle on the page (maybe left it open while eating lunch in the other room). We can simply dismiss these cases by excluding those who have not scrolled for longer than 5 minutes (which I think is possible to extract).
• For retention, it would not be wise to measure visits per week, as users are automatically taken to the page; they can sign in and be brought to the page without engaging with it. So instead, we could measure the number average of interactions (interactions defined the same as the first bullet) per user per week.

I don't want to get into the evaluation and ranking of these metrics because I think that is out of the scope of my focus. Hopefully this is an adequate answer but please give me some feedback since I am still practicing and working on getting better!