Problem Statement and Metrics

LinkedIn feed ranking

1. Problem statement

Design a personalized LinkedIn feed to maximize long-term user engagement. One way to measure engagement is user frequency, i.e, measure the number of engagements per user, but it’s very difficult in practice. Another way is to measure the click probability or Click Through Rate (CTR).

On the LinkedIn feed, there are five major activity types:

• Connections (A connects with B)
• Informational
• Profile
• Opinion
• Site-specific
• Intuitively different activities have very different CTRClick Through Rate. This is important when we decide to build models and generate training data.

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