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Experimentation Methodology and Rigor Questions

Focuses on rigorous experimental methodology and advanced testing approaches needed to produce reliable, actionable results. Topics include statistical power and minimum detectable effect trade offs, multiple hypothesis correction, sequential and interim analysis, variance reduction techniques, heterogenous treatment effects, interference and network effects, bias in online experiments, two stage or multi component testing, multivariate designs, experiment velocity versus validity trade offs, and methods to measure business impact beyond proximal metrics. Senior level discussion includes designing frameworks and practices to ensure methodological rigor across teams and examples of how to balance rapid iteration with safeguards to avoid false positives.

EasyTechnical
56 practiced
Define heterogeneous treatment effects (HTE) and explain why HTE analysis matters for product managers. Provide two concrete product scenarios where HTE would change prioritization or personalization decisions, and briefly describe how you would report actionable HTE findings to stakeholders.
MediumTechnical
63 practiced
You see an experiment with many secondary metrics flagged as significant but the primary metric is null. Propose a defensible process for deciding whether to act on this experiment, including rules for guardrail violations, metric hierarchy, and any additional validation steps you would require before rollout.
HardTechnical
121 practiced
Design a two-stage testing framework where Stage 1 measures short-term engagement lifts and Stage 2 measures longer-term retention and monetization. Explain how to control error rates across stages, allocate sample between stages, criteria for promoting experiments to Stage 2, and decision rules for rollout or additional validation.
EasyTechnical
67 practiced
Explain statistical power, Type I (false positive) and Type II (false negative) errors in the context of product experimentation. Use concrete product examples to illustrate the business costs of both error types and discuss tradeoffs between increasing power, experiment duration, and tolerable error rates.
HardTechnical
65 practiced
Describe step-by-step how to compute bootstrap-based confidence intervals for a ratio metric such as revenue per user. Include the resampling scheme, number of resamples to consider, bias correction if applicable, and how you would present bootstrap intervals and caveats to non-technical stakeholders.

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