ab-test-setup

Designs statistically valid A/B tests and growth experimentation programs with hypothesis frameworks and sample size guidance.

1|Updated Apr 3, 2026
One-click install
npx skills add https://github.com/raheelroy/cyclobrain --skill ab-test-setup-raheelroy
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: ab-test-setup
Source: https://github.com/raheelroy/cyclobrain/tree/main/.claude/skills/ab-test-setup
Command: npx skills add https://github.com/raheelroy/cyclobrain --skill ab-test-setup-raheelroy

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve? Teams often run A/B tests without clear hypotheses, adequate sample sizes, or statistical rigor, leading to false positives, wasted traffic, and wrong product decisions. This Skill provides a structured methodology for designing, running, and analyzing experiments that produce trustworthy results. ## Core Features & Use Cases - Hypothesis & Test Design: Structures hypotheses with a proven framework, selects test types (A/B, A/B/n, MVT, split URL), and defines primary, secondary, and guardrail metrics. - Statistical Rigor: Provides sample size reference tables, duration guidance, significance thresholds, and analysis checklists to avoid the peeking problem and premature test stops. - Experimentation Program Building: Covers ICE prioritization, experiment velocity tracking, playbook documentation, and weekly-to-quarterly cadences for running growth experiments as a continuous engine. - Use Case: A product marketer wants to test a new pricing page headline. The Skill helps calculate the required sample size from the baseline conversion rate, define guardrail metrics like refund rate, and document the result in a reusable experiment playbook. ## Quick Start Ask the assistant to design an A/B test for your pricing page headline change, including hypothesis, sample size, and success metrics.

Frequently Asked Questions about ab-test-setup

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I calculate sample size for an A/B test?▼

Sample size depends on your baseline conversion rate and the minimum detectable effect. For example, a 3% baseline detecting a 20% lift needs about 12k visitors per variant. Use calculators like Evan Miller's or Optimizely's, and see the references/sample-size-guide.md for detailed tables.

How long should I run an A/B test?▼

Run the test until you reach the pre-calculated sample size, typically 2-4 weeks to cover full weekly cycles. Never stop early based on promising results, since peeking before reaching sample size causes false positives.

What is the difference between A/B testing and multivariate testing?▼

A/B testing compares two versions with a single change and needs moderate traffic. Multivariate testing (MVT) tests multiple changes in combinations to isolate interactions, but requires very high traffic volumes to reach significance.

Should I use client-side or server-side A/B testing tools?▼

Client-side tools like PostHog, Optimizely, or VWO modify the page with JavaScript after load, which is quick to implement but can cause flicker. Server-side tools like LaunchDarkly or Split determine variants before render, eliminating flicker but requiring development work.

Why did my A/B test show no significant difference?▼

Inconclusive results usually mean insufficient sample size, too small a change to detect, or a hypothesis that doesn't hold. Check whether you reached the required sample size, then consider a bolder variant or a different page element.

What is ICE scoring for experiment prioritization?▼

ICE scoring rates each hypothesis 1-10 on Impact, Confidence, and Ease, then averages the three scores. Run the highest-scoring experiments first and re-score monthly as data and context change.