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Experiment Design Analysis and Causal Methods Questions

Design and analysis of experiments and causal inference methods for when randomization is not possible. Candidates should know strategies to ensure randomization and evaluate experiment quality compute sample size and minimum detectable effect select and interpret primary and guardrail metrics and design appropriate test duration. Analysis skills include hypothesis testing p values confidence intervals effect size estimation variance estimation and variance reduction segmentation and interaction analysis and robust reporting of uncertainty. This topic covers observational and quasi experimental approaches such as propensity score matching difference in differences and regression discontinuity how to reason about confounding and selection bias and when to prefer a quasi experimental approach over a randomized test. Candidates should be able to translate causal conclusions into actionable guidance recommend follow up analyses and triangulate evidence across methods.

HardTechnical
31 practiced
Design a triangulation strategy for a generative AI safety change: combine an RCT on a subset of anonymized users, observational monitoring of production outputs, and a mechanistic regression model of hallucination risk. Explain how you'd synthesize findings when the RCT shows no effect but observational signals suggest increased hallucinations.
EasyTechnical
25 practiced
List and briefly describe three variance-reduction techniques commonly used in online experiments (e.g., covariate-adjusted analysis, CUPED, blocking). For each technique give one practical limitation or assumption and an example scenario where it yields the largest gains.
MediumTechnical
32 practiced
Describe Regression Discontinuity Design (RDD) for estimating causal effects when an assignment variable crosses a threshold (e.g., credit score cutoff). Explain assumptions (continuity of potential outcomes), bandwidth selection trade-offs, use of local linear regression, and a practical test for manipulation of the running variable (e.g., McCrary test).
MediumTechnical
31 practiced
Explain the meaning of a p-value and list three common misinterpretations. Provide alternative approaches to communicate uncertainty and evidence strength to non-technical stakeholders (e.g., confidence intervals, effect sizes, Bayesian posterior probabilities).
HardTechnical
27 practiced
You are asked to translate causal conclusions from an A/B test into product guidelines for engineering and product teams. Given a statistically significant uplift in a proxy engagement metric but no change in downstream revenue, describe how you would craft recommendations, prioritize follow-ups, and what additional analyses you would require before global rollout.

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