Choose tests for rare-event A/B analysis
Company: HBO
Role: Data Scientist
Category: Statistics & Math
Difficulty: hard
Interview Round: Online Assessment
Overview: This question evaluates expertise in statistical experiment design for rare binary outcomes, covering hypothesis test selection for low-event-rate proportions, sample-size calculation with and without continuity correction, variance reduction via CUPED, confidence-interval construction for risk difference and relative risk, interim alpha spending, and Bayesian Beta–Binomial modeling; it falls under the Statistics & Math domain with emphasis on A/B testing and experimental design. It is commonly asked to assess how a candidate balances statistical validity, power, and sequential monitoring in low-probability A/B tests and requires both conceptual understanding of inference principles and practical application skills such as analytic sample-size derivation and sequential decision criteria.
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