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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

Lesson 5: Experiment setup

Summary

This lesson goes over the main steps of setting up an experiment.

After the planning stage, you need to translate the details of your plan into an actual experiment configuration. At this stage you create an experiment and configure it according to your plan, which includes:

  • Configure the test variants: What part of the user experience will the test change for the users?
  • Select your target audience: For which users will the experience change?
  • Select the metrics you want to track: What are the key success metrics you want to measure? What are important guardrail metrics?

Configure the test variants

To set up an experiment, you need to define the test variants and connect the variants to the product code. Feature flags are the standard mechanism for connecting experiment variants to your product.

Watch this video to get a quick understanding of how feature flags let Confidence control parts of your product remotely.

In Confidence

To get started with feature flags in Confidence, follow the feature flag quickstart. If you want to go through the full steps of setting up an experiment, follow the A/B test or Rollout quickstarts. These guides have onboarded thousands of experimenters at Spotify and are a great way to get started.

Select your target audience

When setting up an experiment, you need to define the target audience for the experiment. This is the group of users that will be included in the experiment. You can define the target audience based on different user attributes, such as country, platform, or user age. What you can target on is determined by what information is passed in when you resolve the feature flag.

Watch this video to get a quick understanding of how targeting and feature flag resolving are related.

Select metrics

Refer to Lesson 3 and Lesson 4 for details on the types of metrics and how to select them.

Sample size and design

One important aspect of the experiment setup is the required sample size. The required sample size is the number of users that you need in your experiment to reach a level of precision in your results that lets you answer the question you have set out to answer. You can control the sample size by setting the allocation, the proportion of the target population that your experiment will include.

Learn more about sample size calculations in Lesson 8.

Reader exercise

What does the allocation control?

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On this page

  1. Configure the test variants

  2. Select your target audience

  3. Select metrics

  4. Sample size and design