ab-test-setup

# A/B Test Setup ## 1️⃣ Purpose & Scope Ensure every A/B test is **valid, rigorous, and safe** before a single line of code is written. - Prevents "peeking" - Enforces statistical power - Blocks invalid hypotheses --- ## 2️⃣ Pre-Requisites You must have: - A clear user problem - Access to an analytics source - Roughly estimated traffic volume ### Hypothesis Quality Checklist A valid hypothesis includes: - Observation or evidence - Single, specific change - Directional expectation - Defined audience - Measurable success criteria --- ## 3️⃣ Hypothesis Lock (Hard Gate) Before designing variants or metrics, you MUST: - Present the **final hypothesis** - Specify: - Target audience - Primary metric - Expected direction of effect - Minimum Detectable Effect (MDE) Ask explicitly: > “Is this the final hypothesis we are committing to for this test?” **Do NOT proceed until confirmed.** --- ## 4️⃣ Assumptions & Validity Check (Mandatory) Explicitly list assumptions about: - Traffic stability - User independence - Metric reliability - Randomization quality - External factors (seasonality, campaigns, releases) If assumptions are weak or violated: - Warn the user - Recommend delaying or redesigning the test --- ## 5️⃣ Test Type Selection Choose the simplest valid test: - **A/B Test** – single change, two variants - **A/B/n Test** – multiple variants, higher traffic required - **Multivariate Test (MVT)** – interaction effects, very high traffic - **Split UR...