0b53f2caa3
New skill: experiment-designer
2.2 KiB
2.2 KiB
name: experiment-designer description: Designs A/B tests from hypotheses and interprets experiment results with statistical rigour. Use when user says "run an experiment", "design an A/B test", "test this feature", "interpret these results", "was this experiment successful", or "what sample size do I need". metadata: author: Mohit Aggarwal version: 1.0.0 category: data-and-metrics tags: [experimentation, data, analytics, ab-testing] documentation: https://github.com/mohitagw15856/pm-claude-skills
Experiment Designer Skill
Purpose
Produce rigorous experiment designs from product hypotheses, and interpret results with statistical and practical significance — so you can defend every decision to a sceptical engineering lead or data scientist.
Two-Phase Process
Phase 1: Experiment Design
Required inputs: hypothesis, primary metric, current baseline, minimum detectable effect (MDE), available sample size per day.
Output:
- Hypothesis restated as: "If we [change], we expect [metric] to [move by X%] because [reason]"
- Control and variant definitions
- Primary metric (one only)
- Secondary guardrail metrics (2-3 max)
- Required sample size (calculated from MDE and baseline)
- Estimated run time in days
- Pre-defined success criteria (before the test runs — no moving goalposts)
- Design risk flags: novelty effects, seasonal confounds, multiple testing issues, network effects, sample ratio mismatch risks
Phase 2: Results Interpretation
Required inputs: control results, variant results, p-value or raw numbers, run duration, any anomalies observed.
Output:
- Statistical significance assessment (p < 0.05 threshold)
- Practical significance: was the lift meaningful for the business, not just real?
- Confidence interval interpretation
- Confounding factors to investigate
- Recommendation: Ship / Iterate / Kill / Run follow-up test
- If "Iterate": specific hypotheses to test next
Quality Checks
- Never interpret results from an underpowered test without flagging it
- Always distinguish statistical from practical significance
- Flag if test was stopped early (peeking problem)
- Note if sample ratio mismatch occurred