ab-test-setup

Designs A/B tests with hypotheses, sample size calculations, metrics, and analysis frameworks.

Updated Dec 22, 2025
One-click install
npx skills add https://github.com/Endsi3g/prospecting-app --skill ab-test-setup-endsi3g
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: ab-test-setup
Source: https://github.com/Endsi3g/prospecting-app/tree/main/.agents/skills/ab-test-setup
Command: npx skills add https://github.com/Endsi3g/prospecting-app --skill ab-test-setup-endsi3g

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve? Teams often run experiments without clear hypotheses, adequate sample sizes, or disciplined analysis, leading to false positives and wasted traffic. This Skill guides the planning, execution, and analysis of A/B tests so results are statistically valid and actionable. ## Core Features & Use Cases - Hypothesis & Test Design: Structures hypotheses with a formal framework and selects the right test type (A/B, A/B/n, MVT, split URL) based on traffic and goals. - Sample Size & Duration Planning: Provides quick-reference tables, duration formulas, and guidance for multiple variants and sequential testing via detailed reference guides. - Metrics & Analysis Framework: Defines primary, secondary, and guardrail metrics, plus checklists for significance testing, segment analysis, and avoiding the peeking problem. - Use Case: A marketer wants to test a new pricing page headline. The Skill calculates required sample size from the baseline conversion rate, defines success and guardrail metrics, sets a fixed duration, and produces a documented test plan. ## Quick Start Ask the assistant to help design an A/B test for a specific page or change, providing your current conversion rate and traffic volume.

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, 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 your 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 when one variant is winning?

No. Stopping early based on peeked results 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 designed for early stopping.

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 catch negative side effects like increased support tickets or refund rates.

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

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