Define and measure project metrics
Company: TikTok
Role: Software Engineer
Category: Analytics & Experimentation
Difficulty: hard
Interview Round: Technical Screen
Define and measure project metrics: For a project of your choice, specify primary outcome metrics, secondary metrics, and guardrails. Precisely define each metric (events, windows, denominators), outline an instrumentation and data-quality plan, and design an experiment or observational evaluation covering sampling, statistical power, expected effect size, seasonality, and heterogeneity. Discuss pitfalls such as metric gaming, selection bias, and Simpson's paradox, and explain how you would monitor and alert on regressions.
Quick Answer: This question evaluates a software engineer's competency in defining outcome, secondary and guardrail metrics, designing instrumentation and data-quality plans, and structuring valid experiments or observational analyses within the Analytics & Experimentation domain.