6/16/2019

Source: splitmetrics.com

Example A/B test

  1. Randomly assign customers to treatments
  2. Measure response(s)
  3. Compare groups to determine how the treatment changes response

Source: Optimizely Blog

Why A/B tests work

By randomizing over a large number of customers, we create groups that are the same, on average.

Any behavioral differences between these groups is caused by the treatments we randomly assigned.

1, 2, 3. Repeat with me. Randomization will set you free.

Workshop plan

  • Test Analysis Basics
    • Randomization checks
    • Analysis
    • Sample size planning
  • When your sample size is big
    • Slice and dice
    • Uplift modeling
    • Causal forests
  • When your sample size is small
    • Pre-test matching
    • Post-stratification
  • Maximizing profits
    • Test & roll
    • Multi-armed bandits
  • When you can’t randomize (time permitting)

About Elea McDonnell Feit

Materials

How to use the materials

We will walk through a set of examples that I created using the R (a statistical programming language).

  • If you don’t know R, let me drive the R syntax so that you can focus on where we are going. Download the slides and follow along.
  • If you are learning R, you should also let me drive. I can answer some R syntax questions along the way, but I don’t want to get stuck in the syntatical mud. The code will be there later when you want to review.
  • If you know R well, download the RMarkdown files and run the code as we go along.

I’m adaptable. Please ask questions so I can calibrate.

Let’s go!