ab-testing

Designs and analyzes A/B tests and growth experimentation programs with statistical rigor.

Updated May 13, 2026
One-click install
npx skills add https://github.com/MarcoBolsa/motor-cotacoes --skill ab-testing-marcobolsa
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: ab-testing
Source: https://github.com/MarcoBolsa/motor-cotacoes/tree/main/.claude/skills/marketingskills/ab-testing
Command: npx skills add https://github.com/MarcoBolsa/motor-cotacoes --skill ab-testing-marcobolsa

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve? Teams often run experiments without clear hypotheses, stop tests too early, or misread results, leading to false conclusions and wasted traffic. This Skill provides a structured framework for planning, running, and analyzing A/B tests and building a continuous experimentation program. ## Core Features & Use Cases - Hypothesis & Test Design: Builds structured hypotheses, selects test types (A/B, A/B/n, MVT), defines primary, secondary, and guardrail metrics, and plans traffic allocation. - Sample Size & Duration Guidance: Provides quick-reference sample size tables, duration formulas, and sequential testing guidance via the references/sample-size-guide.md file. - Experimentation Program Management: Covers ICE prioritization, experiment velocity tracking, playbooks, and documentation templates in references/test-templates.md. - Use Case: A marketer wants to test a new pricing page headline. The Skill calculates the required sample size from the baseline conversion rate, defines metrics, warns against peeking early, and produces a complete test plan. ## Quick Start Ask the assistant to help you design an A/B test for a specific page or change, providing your current conversion rate and traffic volume.

Frequently Asked Questions about ab-testing

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, minimum detectable effect, significance level (usually 95%), and power (usually 80%). Use the quick reference tables in the sample size guide or online calculators like Evan Miller's or Optimizely's.

How long should I run an A/B test?▼

Run until you reach the pre-calculated sample size, with a minimum of one full week to capture day-of-week variation. Avoid running longer than 4-8 weeks due to novelty effects and external factors.

Should I stop an A/B test early if one variant is winning?▼

No. Peeking at results and stopping early inflates false positive rates because early significance can reflect regression to the mean or audience mix shifts. Commit to the pre-calculated duration, or use sequential testing methods if early stopping is required.

What is the difference between an A/B test and a multivariate test?▼

An A/B test compares two versions with a single change, while a multivariate test (MVT) tests combinations of multiple elements simultaneously. MVT requires dramatically more traffic since combinations multiply, so sequential A/B tests are often better for lower-traffic sites.

What metrics should I track in an A/B test?▼

Define three tiers: a primary metric tied directly to your hypothesis, secondary metrics that explain why the change worked, and guardrail metrics that should not get worse. This prevents shipping wins that harm other parts of the business.

What can I do if my site does not have enough traffic for A/B testing?▼

Options include increasing the minimum detectable effect, reducing variants, testing higher-traffic upstream pages, combining traffic across similar pages, or making decisions from qualitative data instead of running an underpowered test.