Determine Key Metrics for Circle's Success Evaluation
Company: Meta
Role: Data Scientist
Category: Analytics & Experimentation
Difficulty: medium
Interview Round: Onsite
##### Scenario
Meta is evaluating a new social feature called Circle (similar to Facebook Groups) and wants to decide how to measure and optimize it.
##### Question
What metrics would you track to measure the success of Circle, given it is the only feature on the platform and guardrail metrics/cannibalization are irrelevant? Using only retrospective data, how would you decide whether Circle should be optimized for small groups (≈5–6 members) or large groups (tens to hundreds)? You are shown three time-series plots of total comments per total posts for three different products with different user bases. Can these lines be directly compared? Explain.
##### Hints
Select a north-star metric; segment by cohort size; normalize metrics before comparison.
Quick Answer: This question evaluates a data scientist's competency in defining north-star metrics and metric frameworks, designing retrospective analyses with bias and confounding mitigation, and normalizing time-series engagement signals for fair comparison.