Design A/B Test for New Amazon Recommendation Module
Company: Amazon
Role: Data Scientist
Category: Analytics & Experimentation
Difficulty: hard
Interview Round: Onsite
Quick Answer: This question evaluates proficiency in online experimentation, statistical inference, metric design, and causal reasoning for a new home-page recommendation feature, covering hypothesis formulation, metric hierarchy and guardrails, sample-size/duration calculation, variance reduction, sequential testing, bias sources, and alternative causal-inference approaches. It is in the Analytics & Experimentation domain and is commonly asked because product and data teams must quantify the causal impact of UI/algorithm changes and balance engagement versus revenue trade-offs; the prompt tests both conceptual understanding of experimental principles and practical application of statistical and causal techniques.