Determine if users need a new feature
Company: Meta
Role: Data Scientist
Category: Analytics & Experimentation
Difficulty: easy
Interview Round: Technical Screen
## Scenario
You are a Data Scientist supporting a consumer product team considering launching a new feature (e.g., a new group-calling/chat feature). You have access to product event logs and can also request additional data collection if needed.
## Tasks
1. **Using the data already available**, how would you identify whether users *need* this feature?
- Define what “need” means in measurable terms.
- If you use an “active user” concept (e.g., **7-day active users**), state your definition clearly.
2. **Assuming you can collect any data you want**, what additional data would you gather to answer the same question better?
3. How would you **measure whether the feature is successful after launch**?
- Propose a metric framework with **primary metric(s)**, **diagnostic metrics**, and **guardrail metrics**.
- Explain how you would align metrics with the feature’s goal and handle trade-offs (e.g., engagement vs. retention vs. quality).
4. How would you address the **novelty effect** (short-term spike after launch that may not persist) when interpreting results?
## Output expectations
Explain your approach end-to-end: problem framing, analysis plan, metrics, experiment or quasi-experiment design, and key pitfalls (bias/confounding, seasonality, logging gaps, metric gaming).
Quick Answer: This question evaluates a data scientist's competency in product analytics, causal inference, experiment design, metric definition, instrumentation, and diagnostic monitoring for assessing user need and feature impact.