How would you compare Facebook vs Instagram Stories?
Company: Meta
Role: Data Scientist
Category: Analytics & Experimentation
Difficulty: easy
Interview Round: Onsite
You work on short-form ephemeral content. Both **Facebook Stories** and **Instagram Stories** exist, and leadership asks: **Which product should we invest in, and how do we measure success without being misled by cannibalization?**
Design an analysis/experiment plan:
1. Define **primary**, **diagnostic**, and **guardrail** metrics for Stories.
2. Explain how you would compare Facebook vs Instagram Stories given:
- Overlapping users across apps
- Potential cannibalization of Feed/Reels and messaging
- Different baselines and user intents per app
3. Propose at least one **causal identification strategy** (e.g., A/B test, geo experiment, diff-in-diff) and discuss key biases/confounders.
4. Describe what decision you would recommend given possible outcomes (e.g., engagement up but revenue down; creator supply up but user retention flat).
Overview: This question evaluates a data scientist's competency in product analytics, experimental design, and causal inference for short-form ephemeral content, including metric definition, overlap and cannibalization assessment, and trade-off analysis.