Calculate expected value for A/B test results
Last updated: May 26, 2026
Quick Overview
Given the following scenario about user conversion, calculate the the sample size needed.
JPMorgan
May 26, 202690
6
2,690 solved
Given the following scenario about user conversion, calculate the the sample size needed.
JPMorgan values data-driven decision making. This Take-home Project question assesses whether you can design experiments, interpret results correctly, and avoid common statistical pitfalls like p-hacking or Simpson's paradox.
What the Interviewer Expects
- Derive results from first principles when needed
- Handle complex scenarios with multiple interacting variables
- Design experiments that account for real-world complications
- Discuss advanced topics: Bayesian methods, causal inference, resampling
- Connect statistical concepts to business decision-making
- Identify subtle errors in reasoning (Simpson's paradox, survivorship bias)
Key Topics to Cover
How to Approach This
- Define your hypotheses (H0 and H1) clearly before performing any test.
- Calculate required sample size BEFORE running an experiment, using power analysis.
- Remember the Central Limit Theorem: sample means become approximately normal with large n.
- Watch for Simpson's paradox. Always segment data by key dimensions.
- Distinguish between statistical significance and practical significance.
Possible Follow-up Questions
- How would you design a follow-up experiment based on these results?
- How would you explain this result to a non-technical audience?
- How would you handle multiple comparisons?
- What alternative statistical method could you use here?
Sharpen Your Skills on Codemia
Practice similar problems with our interactive workspace, get AI feedback, and track your progress.
Browse Statistics QuestionsSample Answer
Problem Formulation
In this scenario, we want to conduct an A/B test to measure user conversion rates between two groups: the control group (A) and the treatment group (B). We need to determine the sample size required t...
Solution Approach
To compute the sample size, we need the following steps:
- Define parameters: Establish , , , , and eta.
- Calculate pooled conversion rate...
Submit Your Answer
