Experiment designer
ProblemExperiments launch without a hypothesis or success criteria, so results get argued about.
Test a one-page checkout vs three steps · baseline conversion 3% · 8,000 checkouts/week
Hypothesis: because 40% drop at the address step, one page will raise conversion for mobile users.
To detect +15% relative (3.0 → 3.45%) at 80% power: ~24,000 per arm ≈ 6 weeks.
Decision rule: ship if p < 0.05 and refund rate is unchanged.
Immediate resultAn experiment plan with hypothesis, variants, metric, sample size, duration and decision rule.


