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  • Confidence Bootcamp
    • My learning
    • Intro to experimentation
      • Introduction
      • Lesson 1: Why you should experiment
      • Lesson 2: Experiment hypothesis
      • Lesson 3: Success and guardrail metrics
      • Lesson 4: Success metrics
      • Lesson 5: Set up your experiment
      • Lesson 6: Calculation frequency
      • Lesson 7: Target audience
      • Lesson 8: Sample size
      • Lesson 9: Quality assurance
      • Lesson 10: Run your experiment
      • Lesson 11: Evaluate your experiment and make a decision
      • Lesson 12: A/B tests and rollouts
      • Course wrap up
    • Intro to metrics
      • Introduction
      • Lesson 1: What is a metric?
      • Lesson 2: Metric roles
      • Lesson 3: Time considerations
      • Lesson 4: Capturing behavior
      • Lesson 5: Strategic metrics
      • Lesson 6: Interpretability
      • Lesson 7: Feasibility and sensitivity
      • Lesson 8: Variance reduction
      • Lesson 9: Select metrics
      • Lesson 10: Segment-level analysis
      • Course wrap up
    • Scientific product development
      • Introduction
      • Lesson 1: Why you should experiment
      • Lesson 2: The scientific method
      • Lesson 3: Randomized controlled trials
      • Lesson 4: Experiment hypothesis
      • Lesson 5: Case study
        • Case study
        • Answers to case study
      • Lesson 6: Why do we need statistics?
      • Lesson 7: Success metrics
      • Lesson 8: Detectable effects and sample size
      • Lesson 9: Make a decision
      • Course wrap up
    • A primer on hypothesis testing
      • Introduction
      • Lesson 1: Introduction to hypothesis testing
      • Lesson 2: True vs estimated effects
      • Lesson 3: Sampling distribution of the difference-in-means estimator
      • Lesson 4: Z-tests and how to reject the null hypothesis
      • Lesson 5: False postive rate and alpha
      • Lesson 6: True positive rate, MDE, and power
      • Course wrap up
    • Intro to Feature Flags
      • Introduction
      • Lesson 1: What is a feature flag?
      • Lesson 2: Lifecycle of a feature flag
      • Lesson 3: Clients
      • Lesson 4: Evaluation context and targeting
    • Sample size calculation - I
      • Introduction
      • Lesson 1: What is the required sample size?
      • Lesson 2: Alpha and power
      • Lesson 3: Baseline mean and variance
      • Lesson 4: Sample size playground - I
    • Sample size calculation - II
      • Introduction
      • Lesson 1: Multi-metric decision making
      • Lesson 2: Number of success metrics
      • Lesson 3: Number of guardrail metrics
      • Lesson 4: Number of comparisons
      • Lesson 5: Sample size playground - II
    • Sample size calculation - III
      • Introduction
      • Lesson 1: Binary metrics
      • Lesson 2: Treatment group proportions
      • Lesson 3: Variance reduction
      • Lesson 4: Sequential testing and sample size
      • Lesson 5: Sample size playground - III
    • Advance your experimentation
      • Introduction
      • Lesson 1: Guardrail metrics with non-inferiority margins
      • Lesson 2: Choose evaluation frequency
      • Lesson 3: Metrics' roles in experiments
      • Lesson 4: Cumulative holdback evaluations
    • Experimentation culture
      • Introduction
      • Lesson 1: Onboarding into experimentation
      • Lesson 2: Empowering experimentation champions
      • Lesson 3: Sustaining the experimentation culture
    • Videos

Welcome to Sample size calculation — level III

Sample size calculation — level III is an asynchronous, interactive, self-paced course that teaches you the fundamental concepts of how to calculate the required sample size for experiments. This course focuses on building intuition for why you need to plan the sample size before the experiment and what settings and aspects that affect the required sample size.

In this course, you'll learn about some of the more mathematical aspects of sample size calculation. You learn about variance reduction and how it reduces the required sample size. You also get to build intuition for how the sample size calculation differs between binary and continuous metrics, and how the treatment group proportions affect the required sample size. Finally, you get to play around with the complete sample size calculator, accounting for all the aspects covered in all three sample size courses.

Note

There are quiz questions throughout the course to help you check your understanding of the material. Complete each lesson's questions to track your progress.

Before you begin

This is the third and final level of the Sample Size Calculation course series. If you haven't already, complete the previous levels before starting this course:

  • Sample size calculation - level I
  • Sample size calculation - level II

Lessons

This course consists of the following lessons:

Lesson 1: Binary metrics

Understand how sample size calculations differ between binary and continuous metrics.

Not completed

Lesson 2: Treatment group proportions

Build intuition for why the relative sizes of the treatment groups affect the required sample size.

Not completed

Lesson 3: Variance Reduction

Learn why variance reduction might as well be called sample size reduction.

Not completed

Lesson 4: Sequential testing and sample size

Learn how sequential tests trade off extra data for the ability to monitor results during an experiment.

Not completed

Lesson 5: Sample size playground

Build intuition for sample size calculation by playing with different settings in the playground.

Not completed

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  1. Before you begin

  2. Lessons