Diagnose Decline in User Engagement and Experience Quality
Company: TikTok
Role: Data Scientist
Category: Analytics & Experimentation
Difficulty: medium
Interview Round: Technical Screen
##### Scenario
Product metrics deep-dive and causal inference discussion with a manager concerned about growth and experience quality.
##### Question
a) You notice a steady decline in daily active users over several weeks. What metrics would you define and what experiment or analysis would you design to diagnose the issue?
b) A manager wants to quantify how users’ network speed affects TikTok usage, but only observational data are available. Describe a suitable causal-inference approach and how you would explain its validity to a non-technical stakeholder.
##### Hints
Think retention, cohorts, segmentation, IV / propensity weighting, clearly communicate assumptions.
Quick Answer: This question evaluates a data scientist's competency in defining product metrics, diagnosing declines in user engagement through retention, cohort and segmentation analysis, designing experiments or analyses, and applying causal-inference reasoning with observational data.