Calculate variance for user retention

Last updated: January 30, 2026

Quick Overview

Given the following scenario about user conversion, calculate the the p-value.

Netflix
Statistics & Math
Data Scientist
Netflix
January 30, 2026
Data Scientist
Technical Screen
Statistics & Math
Medium

1

4

139 solved


Given the following scenario about user conversion, calculate the the p-value.

Statistics questions at Netflix test your ability to reason quantitatively and design rigorous experiments. This Technical Screen question evaluates your understanding of statistical inference and its application to business decisions.

What the Interviewer Expects
  • Set up the problem formally with proper notation
  • Apply the correct statistical test with clear justification
  • Interpret results with appropriate caveats and confidence levels
  • Discuss practical significance vs statistical significance
  • Identify potential confounders and how to address them
Key Topics to Cover
Probability distributions
Power analysis and sample size calculation
Bayesian vs frequentist inference
Causal inference basics
Conditional probability and Bayes theorem
How to Approach This
  1. Define your hypotheses (H0 and H1) clearly before performing any test.
  2. Calculate required sample size BEFORE running an experiment, using power analysis.
  3. Remember the Central Limit Theorem: sample means become approximately normal with large n.
  4. Watch for Simpson's paradox. Always segment data by key dimensions.
  5. Distinguish between statistical significance and practical significance.
Possible Follow-up Questions
  • What alternative statistical method could you use here?
  • How would you handle multiple comparisons?
  • How would you design a follow-up experiment based on these results?
Sharpen Your Skills on Codemia

Practice similar problems with our interactive workspace, get AI feedback, and track your progress.

Browse Statistics Questions
Sample Answer
Setting Up the Problem

Start by formalizing the problem: 1. **Define the hypotheses**: H0 (null hypothesis) and H1 (alternative). Be precise about what you're testing. 2. ...

Solution Approach

**Compute the test statistic**: Apply the appropriate formula using the sample data. **Find the p-value**: The probability of observing a result this...


Submit Your Answer
Markdown supported

Related Questions